Fix pre-commit GitHub Actions job (#1708)

For some reason, editable pip installs are now broken, which means that
they will break the pre-commit workflow due to the `pip install -e .`
instruction.

Since the normal install is unaffected, we can just drop the `-e` switch.
It does not matter which mode is used, since the environment is only
used for linting.

.github/workflows/pre-commit.yml

@@ -25,7 +25,7 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install -e ".[dev]"
+        pip install ".[dev]"
     - name: Cache pre-commit tools
       uses: actions/cache@v3
       with: