Add --fetch-HEAD completions to bash

etc/bash_completion.d/brew

@@ -343,7 +343,7 @@ _brew_outdated() {
   local cur="${COMP_WORDS[COMP_CWORD]}"
   case "$cur" in
     --*)
-      __brewcomp "--quiet --json=v1"
+      __brewcomp "--quiet --json=v1 --fetch-HEAD"
       return
       ;;
   esac
@@ -520,6 +520,7 @@ _brew_upgrade() {
         --cleanup
         --debug
         --verbose
+        --fetch-HEAD
         "
       return
       ;;