test: rename credential test fixtures to avoid GitGuardian false positives

Author: frankbria

tests/core/test_credentials_per_user.py

@@ -33,9 +33,9 @@
 
 pytestmark = pytest.mark.v2
 
-ANTHROPIC_A = "sk-ant-api03-" + "a" * 32
-ANTHROPIC_B = "sk-ant-api03-" + "b" * 32
-GITHUB_A = "ghp_" + "a" * 36
+ANTHROPIC_A = "test-anthropic-key-" + "a" * 20
+ANTHROPIC_B = "test-anthropic-key-" + "b" * 20
+GITHUB_A = "test-github-token-" + "a" * 20
 
 
 @pytest.fixture(autouse=True)