bin/get-pick-list.sh: sha1 commits can be smaller than 8 chars

The script only handles commits with "Fixes: <sha1>" where <sha1> is
equal or great than 8 chars. But <sha1> can be smaller, like 7 chars.

This commit relax the restriction to handle <sha1> 4 or more chars.

Fixes: 533fead423 ("bin/get-pick-list.sh: tweak the commit sha matching pattern")

Acked-by: Eric Engestrom <eric.engestrom@intel.com>
Signed-off-by: Juan A. Suarez Romero <jasuarez@igalia.com>

bin/get-pick-list.sh

@@ -32,7 +32,7 @@ is_sha_nomination()
 {
 	fixes=`git show --pretty=medium -s $1 | tr -d "\n" | \
 		sed -e 's/'"$2"'/\nfixes:/Ig' | \
-		grep -Eo 'fixes:[a-f0-9]{8,40}'`
+		grep -Eo 'fixes:[a-f0-9]{4,40}'`
 
 	fixes_count=`echo "$fixes" | grep "fixes:" | wc -l`
 	if test $fixes_count -eq 0; then