Revert "ci: Remove --depth=1000 in doing Flutter clone, to be added back later"

This reverts commit 2b99578.

Fixes: #1204

Signed-off-by: Zixuan James Li <[email protected]>

Author: PIG208

.github/workflows/ci.yml

@@ -18,9 +18,12 @@ jobs:
         distribution: temurin
 
     - name: Clone Flutter SDK
-      # TODO(#1204) reinstate shallow clone with --depth=1000 and its corresponding comment here
+      # We can't do a depth-1 clone, because we need the most recent tag
+      # so that Flutter knows its version and sees the constraint in our
+      # pubspec is satisfied.  It's uncommon for flutter/flutter to go
+      # more than 100 commits between tags.  Fetch 1000 for good measure.
       run: |
-        git clone -b main https://github.com/flutter/flutter ~/flutter
+        git clone --depth=1000 -b main https://github.com/flutter/flutter ~/flutter
         TZ=UTC git --git-dir ~/flutter/.git log -1 --format='%h | %ci | %s' --date=iso8601-local
         echo ~/flutter/bin >> "$GITHUB_PATH"