delete action, will use drone instead

.github/workflows/docs.yml

@@ -1,19 +0,0 @@
-name: Build docs with nix and Material for mkDocs
-on:
-    push:
-
-jobs:
-    build-docs:
-        runs-on: ubuntu-latest
-        steps:
-            - uses: actions/checkout@v4
-            - name: Nix action dependencies
-              run: |
-                apt update -y
-                apt upgrade -y
-            - uses: cachix/install-nix-action@v27
-            - name: Build package from flake
-              run: nix build .#docs
-            - uses: https://gitea.com/actions/gitea-upload-artifact@v4
-              with:
-                path: ./result