[chore](trx-rs): run reuse lint directly instead of Docker action

The host-executor runners have no Docker daemon, so fsfe/reuse-action
(a Docker action) fails with "Cannot connect to the Docker daemon". Call
the reuse CLI directly; it is baked into the runner image.

Assisted-By: Claude Code (claude-opus-4)
Claude-Session: https://claude.ai/code/session_01NFpGtGTWUEYXLwZeZs2RAV
Signed-off-by: Stan Grams <sjg@haxx.space>

.gitea/workflows/ci.yml

@@ -103,4 +103,7 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - name: REUSE compliance
-        uses: fsfe/reuse-action@v5
+        # `reuse` CLI instead of fsfe/reuse-action: the latter is a Docker
+        # action, which the host-executor runners cannot run. `reuse` is baked
+        # into the runner image (see container/Containerfile).
+        run: reuse lint