Remove deprecated experimental invariant_booleans lint rule (dart-lang/test_descriptor#42)

pkgs/test_descriptor/analysis_options.yaml

diff --git a/pkgs/test_descriptor/analysis_options.yaml b/pkgs/test_descriptor/analysis_options.yaml
index 56bbaad..200a3d4 100644
--- a/pkgs/test_descriptor/analysis_options.yaml
+++ b/pkgs/test_descriptor/analysis_options.yaml
@@ -26,7 +26,6 @@
     - empty_statements
     - hash_and_equals
     - implementation_imports
-    - invariant_booleans
     - iterable_contains_unrelated_type
     - library_names
     - library_prefixes