[Linux] docs: `brew bump-formula-pr` now removes the Linux bottle line

- This had been a continual source of pain, and was fixed by 359dc967.
- Now, `brew bump-formula-pr` should be seamless on Linux, which means
  less work for maintainers, which means fewer words are needed here.

bottle: Elide root_url only if it is the default

Elide root_url only if it is precisely equal to the default root_url.
Eliding root_url when a prefix matches the default also elides
a custom root_url such as https://linuxbrew.bintray.com/bottles-bio.

doctor: remove DYLD checks

Dockerfile: install 'netbase' apt package

build: bump rubyzip from 2.0.0 to 2.1.0 in /docs

Bumps [rubyzip](https://github.com/rubyzip/rubyzip) from 2.0.0 to 2.1.0.
- [Release notes](https://github.com/rubyzip/rubyzip/releases)
- [Changelog](https://github.com/rubyzip/rubyzip/blob/master/Changelog.md)
- [Commits](https://github.com/rubyzip/rubyzip/compare/v2.0.0...v2.1.0

)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

build: bump github-pages from 203 to 204 in /docs

Bumps [github-pages](https://github.com/github/pages-gem) from 203 to 204.
- [Release notes](https://github.com/github/pages-gem/releases)
- [Commits](https://github.com/github/pages-gem/compare/v203...v204

)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

build: bump html-proofer from 3.15.0 to 3.15.1 in /docs

Bumps [html-proofer](https://github.com/gjtorikian/html-proofer) from 3.15.0 to 3.15.1.
- [Release notes](https://github.com/gjtorikian/html-proofer/releases)
- [Commits](https://github.com/gjtorikian/html-proofer/compare/v3.15.0...v3.15.1

)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

system_config: ignore HOMEBREW_*_GIT_REMOTE.

bump-formula-pr: delete linux sha256 line if required

Co-Authored-By: Mike McQuaid <mike@mikemcquaid.com>

These aren't interesting enough to show in `brew config` as they
duplicate other data already displayed.

Merge pull request #6943 from Homebrew/dependabot/bundler/Library/Homebrew/unicode-display_width-1.6.1

build: bump unicode-display_width from 1.6.0 to 1.6.1 in /Library/Homebrew

Bumps [unicode-display_width](https://github.com/janlelis/unicode-display_width) from 1.6.0 to 1.6.1.
- [Release notes](https://github.com/janlelis/unicode-display_width/releases)
- [Changelog](https://github.com/janlelis/unicode-display_width/blob/master/CHANGELOG.md)
- [Commits](https://github.com/janlelis/unicode-display_width/compare/v1.6.0...v1.6.1

)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

build: bump unicode-display_width from 1.6.0 to 1.6.1 in /docs

cleanup: fix portable ruby bundler removal.

Bumps [unicode-display_width](https://github.com/janlelis/unicode-display_width) from 1.6.0 to 1.6.1.
- [Release notes](https://github.com/janlelis/unicode-display_width/releases)
- [Changelog](https://github.com/janlelis/unicode-display_width/blob/master/CHANGELOG.md)
- [Commits](https://github.com/janlelis/unicode-display_width/compare/v1.6.0...v1.6.1

)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Need to ensure portable rubies are removed last and pass more paramaters to
git clean.

Catalina upgrades causes Homebrew to break when you run brew cleanup.  Catalina has Ruby 2.6 installed, so the portable Ruby version is not needed.

If you have /usr/local/Homebrew/Library/Homebrew/vendor/portable-ruby (for older OS X versions), then the cleanup tool will nuke everything in usr/local/Homebrew/Library/Homebrew/vendor/bundle/ruby. You will need to brew update-reset to get back the old packages.

audit: add uses_from_macos dependency ordering

ARGV: Replaces usages of ARGV.force? with Homebrew.args.force?

dev-cmd/bottle: run `sudo --purge` non-interactively.

This should avoid hanging if permissions are not granted.

build: bump parallel_tests from 2.30.0 to 2.30.1 in /Library/Homebrew

build: bump ffi from 1.11.3 to 1.12.1 in /docs

cmd/gist-logs: Fix bug with parsing of command-line arguments

- A user reported the following error when running `brew gist-logs`,
reproducible with any formula:

```
$ brew gist-logs rustup-init
Error: undefined method `length' for nil:NilClass
Please report this bug:
  https://docs.brew.sh/Troubleshooting
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/cmd/gist-logs.rb:145:in `gist_logs'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/brew.rb:102:in
```

- From what I can tell, `gist_logs_args.parse` had ended up in the wrong
  method. The `gistify_logs` method already has `formula` (ie the
  formula name) passed into it. But it's the `gist_logs` method that needs
  to do the argument parsing. This was discovered by looking at some other
  recently changed ARGV => Homebrew.args code like cmd/info.

Bumps [ffi](https://github.com/ffi/ffi) from 1.11.3 to 1.12.1.
- [Release notes](https://github.com/ffi/ffi/releases)
- [Changelog](https://github.com/ffi/ffi/blob/master/CHANGELOG.md)
- [Commits](https://github.com/ffi/ffi/compare/1.11.3...1.12.1

)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Bumps [parallel_tests](https://github.com/grosser/parallel_tests) from 2.30.0 to 2.30.1.
- [Release notes](https://github.com/grosser/parallel_tests/releases)
- [Commits](https://github.com/grosser/parallel_tests/compare/v2.30.0...v2.30.1

)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

dev-cmd/bottle: add HOMEBREW_BOTTLE_SUDO_PURGE.

Add environment variable to optionally run `sudo purge` a few times to
potentially work around #6539.

Reuse `test_args` and `postinstall_args` methods