workflows: rename `update-manpage` to `update-man-completions`

.github/workflows/update-manpage.yml → .github/workflows/update-man-completions.yml

@@ -3,7 +3,7 @@ name: Update maintainers, manpage and completions
 on:
   push:
     paths:
-      - .github/workflows/update-manpage.yml
+      - .github/workflows/update-man-completions.yml
       - README.md
       - Library/Homebrew/cmd/**
       - Library/Homebrew/dev-cmd/**
@@ -41,7 +41,7 @@ jobs:
         run: |
           git fetch origin
 
-          BRANCH=update-manpage
+          BRANCH=update-man-completions
           echo "::set-output name=branch::${BRANCH}"
 
           if git ls-remote --exit-code --heads origin "$BRANCH"; then
@@ -62,7 +62,7 @@ jobs:
                     "$GITHUB_WORKSPACE/manpages/brew.1" \
                     "$GITHUB_WORKSPACE/completions"
             git commit -m "Update maintainers, manpage and completions." \
-                       -m "Autogenerated by the [update-manpage](https://github.com/Homebrew/brew/blob/HEAD/.github/workflows/update-manpage.yml) workflow."
+                       -m "Autogenerated by the [update-man-completions](https://github.com/Homebrew/brew/blob/HEAD/.github/workflows/update-man-completions.yml) workflow."
             echo "::set-output name=committed::true"
             if [ -n "$BRANCH_EXISTS" ]; then
               echo "::set-output name=pull_request::true"