add changelog check workflow

.github/workflows/changelog-existence.yml

@@ -0,0 +1,40 @@
+# **what?**
+# Checks that a file has been committed under the /.changes directory
+# as a new CHANGELOG entry.  Cannot check for a specific filename as
+# it is dynamically generated by change type and timestamp.
+# This workflow runs on pull_request_target because it requires
+# secrets to post comments.
+
+# **why?**
+# Ensure code change gets reflected in the CHANGELOG.
+
+# **when?**
+# This will run for all PRs going into main.  It will
+# run when they are opened, reopened, when any label is added or removed
+# and when new code is pushed to the branch.  The action will get
+# skipped if the 'Skip Changelog' label is present is any of the labels.
+
+name: Check Changelog Entry
+
+on:
+  pull_request_target:
+    types: [opened, reopened, labeled, unlabeled, synchronize]
+    paths-ignore: ['.changes/**', '.github/**', 'tests/**', 'third-party-stubs/**', '**.md', '**.yml']
+
+  workflow_dispatch:
+
+defaults:
+  run:
+    shell: bash
+
+permissions:
+  contents: read
+  pull-requests: write
+
+jobs:
+  changelog:
+    uses: dbt-labs/actions/.github/workflows/changelog-existence.yml@main
+    with:
+      changelog_comment: 'Thank you for your pull request! We could not find a changelog entry for this change. For details on how to document a change, see [the contributing guide](https://github.com/dbt-labs/dbt-common/blob/main/CONTRIBUTING.md#adding-changelog-entry).'
+      skip_label: 'Skip Changelog'
+    secrets: inherit

pyproject.toml

@@ -58,6 +58,7 @@ lint = [
 test = [
     "pytest~=7.3",
     "pytest-xdist~=3.2",
+    "pytest-cov~=4.1",
     "hypothesis~=6.87"
 ]
 build = [
@@ -91,7 +92,7 @@ description = "Env for running development commands for testing"
 features = ["test"]
 
 [tool.hatch.envs.test.scripts]
-unit = "- python -m pytest {args:tests/unit}"
+unit = "python -m pytest --cov=dbt_common --cov-report=xml {args:tests/unit}"
 
 
 ### Linting settings, envs & scripts