Add pre-commit action workflow

This patch adds a GitHub Action workflow to run
[pre-commit](https://pre-commit.com/) to run checks on changed files.

The following checks are active:
 - check-added-large-files: prevent large files from being committed
 - check-case-conflict: checks for files that would conflict in
   case-insensitive filesystems
 - check-toml, check-yaml: check toml/yaml parseability
 - end-of-file-fixer: make sure files end with newline
 - mixed-line-ending: check for mixed line endings
 - trailing-whitespace: no trailing whitespace

To configure `pre-commit` to run locally when committing: i) install
pre-commit and ii) install the hook with `pre-commit install`.

.github/workflows/pre-commit.yml

@@ -0,0 +1,13 @@
+name: pre-commit
+
+on:
+  pull_request:
+  push:
+    branches: [master]
+
+jobs:
+  pre-commit:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    - uses: pre-commit/action@2c7b3805fd2a0fd8c1884dcaebf91fc102a13ecd # v3.0.1

.pre-commit-config.yaml

@@ -0,0 +1,11 @@
+repos:
+-   repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v3.2.0
+    hooks:
+     - id: check-added-large-files
+     - id: check-case-conflict
+     - id: check-toml
+     - id: check-yaml
+     - id: end-of-file-fixer
+     - id: mixed-line-ending
+     - id: trailing-whitespace