Remove ci_lint.sh

After the previous commit, it doesn't do much, only passes the linting
exceptions file on the command line. Instead, make the lint.exceptions
file the default for that argument (if it exists), and remove the shell
script.

.github/workflows/checks-main.yml

@@ -25,4 +25,4 @@ jobs:
         run: ./tools/lint/test/run.py
 
       - name: Lint all tests
-        run: ./tools/scripts/ci_lint.sh
+        run: ./tools/lint/lint.py test/

.github/workflows/checks-pr.yml

@@ -39,4 +39,4 @@ jobs:
           for file in $CHANGED; do
             echo $file
           done
-          ./tools/scripts/ci_lint.sh $CHANGED
+          ./tools/lint/lint.py $CHANGED

tools/lint/lint.py

@@ -97,7 +97,11 @@ def lint(file_names, features):
     if args.exceptions:
         exceptions = lib.exceptions.parse(args.exceptions)
     else:
-        exceptions = dict()
+        try:
+            with open('lint.exceptions', 'r') as default_exceptions:
+                exceptions = lib.exceptions.parse(default_exceptions)
+        except FileNotFoundError:
+            exceptions = dict()
 
     files = [path for _path in args.path for path in collect_files(_path)]
     file_count = len(files)