fix: use gitea runner instead of ubuntu-latest

.gitea/workflows/ci.yml

@@ -1,14 +1,10 @@
 name: CI
 
-on:
-  push:
-    branches: [main]
-  pull_request:
-    branches: [main]
+on: [push, pull_request]
 
 jobs:
   test:
-    runs-on: ubuntu-latest
+    runs-on: gitea
     steps:
       - name: Checkout
         run: |
@@ -19,12 +15,12 @@ jobs:
         run: |
           python3 -m pip install --upgrade pip
 
-      - name: Install
+      - name: Install dependencies
         run: |
           python3 -m pip install pytest ruff
           python3 -m pip install -e ".[dev]"
 
-      - name: Test
+      - name: Run tests
         run: |
           python3 -m pytest tests/ -v --tb=short