Selectively disable linting for docs/custom_conf.py

Re-enable linting for docs/custom_conf.py (removing global noqa), but
selectively disable tests that fail, as much of this code is based on
sphinx-docs-starter-pack/custom_conf.py, which does not use the same
linting as this project.

docs/custom_conf.py

@@ -12,7 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-# ruff: noqa
 import datetime
 import pathlib
 import sys
@@ -100,7 +99,7 @@ def _compute_navigation_tree(context):
 #   -H 'Accept: application/vnd.github.v3.raw' \
 #   https://api.github.com/repos/canonical/<REPO> | jq '.created_at'
 
-copyright = '%s, %s' % (datetime.date.today().year, author)
+copyright = '%s, %s' % (datetime.date.today().year, author)  # noqa: A001
 
 ## Open Graph configuration - defines what is displayed as a link preview
 ## when linking to the documentation from another website (see https://ogp.me/)

pyproject.toml

@@ -160,6 +160,7 @@ ignore = [
     # Unnecessary `tuple` call (rewrite as a literal)
     "C408",
 ]
+
 [tool.ruff.lint.per-file-ignores]
 "test/*" = [
     # All documentation linting.
@@ -181,6 +182,16 @@ ignore = [
     "S605",  # Starting a process with a shell: seems safe, but may be changed in the future; consider rewriting without `shell`
     "S607",  # Starting a process with a partial executable path
 ]
+"docs/custom_conf.py" = [
+    "D100",  # Missing docstring in public module
+    "D101",  # Missing docstring in public class
+    "D102",  # Missing docstring in public method
+    "D103",  # Missing docstring in public function
+    "E266",  # Too many leading `#` before block comment
+    "I001",  # Import block is un-sorted or un-formatted
+    "RUF003",  # Comment contains ambiguous unicode characters (EN DASH, RIGHT SINGLE QUOTATION MARK)
+    "UP031",  # Use format specifiers instead of percent format
+]
 
 [tool.ruff.lint.pydocstyle]
 convention = "google"