switch to babi-grammars for syntax

tests/conftest.py

@@ -0,0 +1,17 @@
+import json
+
+import pytest
+
+from babi.highlight import Grammars
+
+
+@pytest.fixture
+def make_grammars(tmpdir):
+    grammar_dir = tmpdir.join('grammars').ensure_dir()
+
+    def make_grammars(*grammar_dcts):
+        for grammar in grammar_dcts:
+            filename = f'{grammar["scopeName"]}.json'
+            grammar_dir.join(filename).write(json.dumps(grammar))
+        return Grammars(grammar_dir)
+    return make_grammars