Fix workspace file list not refreshed when git status is empty

[qiangxue1206]

What

WorkspaceFiles.vue#refresh() ignored an empty git status --porcelain result
(if (data) { this.parseStatus(data) }). A clean working tree produces an empty
string, so the file list kept stale entries right after any operation that makes
the tree clean — commit, revert, and push.

Symptom: after a successful commit the just-committed files stay in the list, so
it looks like the commit failed; only a full page reload (F5) fixes the display.

Fix

Apply the result unconditionally:

this.parseStatus(data || '');

parseStatus('') yields an empty item list, so both panels are correctly cleared.

Notes

• Secondary case: after a commit, showCommitDialog() calls the local
  this.refresh() instead of this.$emit('refresh') (used by revert()), so the
  sibling panel isn't refreshed either. The if (data) guard is the primary
  cause, but $emit('refresh') there would keep both panels consistent.
• Reproduced with 8.3.1 on Airflow 3.3.2 (FAB auth manager, Docker Compose).
• Not built locally; relying on CI for the build/test check.