GHA: replace uv with bare python (#196)

Replace installer Action `astral-sh/setup-uv` and the `uv` tool with
bare Python invocation. The specific script doesn't have
dependencies, and faster to run as-is. It also eliminates a GHA and
tool dependency, and the need for GHA caching.

Author: vszakats

.github/workflows/ci.yml

@@ -28,13 +28,12 @@ jobs:
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
         with:
           repository: curl/curl-fuzzer
-      - name: Install uv
-        uses: astral-sh/setup-uv@b75a909f75acd358c2196fb9a5f1299a9a8868a4 # v6
       - name: Set matrix
         id: set-matrix
         run: |
           . ./scripts/fuzz_targets
-          uv run generate_matrix | tee $GITHUB_OUTPUT
+          cd src/curl_fuzzer_tools
+          python3 -m generate_matrix | tee $GITHUB_OUTPUT
 
   BuildFuzzers:
     runs-on: ubuntu-latest