chore: Fix spelling

Merge https://github.com/google/adk-python/pull/2447

This PR corrects misspellings identified by the [check-spelling action](https://github.com/marketplace/actions/check-spelling)

The misspellings have been reported at https://github.com/jsoref/adk-python/actions/runs/16840838898/attempts/1#summary-47711379253

The action reports that the changes in this PR would make it happy: https://github.com/jsoref/adk-python/actions/runs/16840839269/attempts/1#summary-47711380479

Note: while I use tooling to identify errors, the tooling doesn't _actually_ provide the corrections, I'm picking them on my own. I'm a human, and I may make mistakes.

I've included a couple of changes to make CI happy. Personally, I object to CI being in a state of "random drive by person who adds a blank line in the middle of a file must fix all the preexisting bugs in the file", but that appears to be the state for this repository.

COPYBARA_INTEGRATE_REVIEW=https://github.com/google/adk-python/pull/2447 from jsoref:spelling d85398e7fd154d124d477c6af6181481a01f34e0
PiperOrigin-RevId: 827629615

tests/unittests/a2a/utils/test_agent_card_builder.py

@@ -331,7 +331,7 @@ class TestHelperFunctions:
     assert result == "I should do my work and it will be mine."
 
   def test_replace_pronouns_case_insensitive(self):
-    """Test _replace_pronouns with case insensitive matching."""
+    """Test _replace_pronouns with case-insensitive matching."""
     # Arrange
     text = "YOU should do YOUR work and it will be YOURS."
 
@@ -1073,7 +1073,7 @@ class TestExampleExtractionFunctions:
     assert result is None
 
   def test_extract_examples_from_instruction_case_insensitive(self):
-    """Test _extract_examples_from_instruction with case insensitive matching."""
+    """Test _extract_examples_from_instruction with case-insensitive matching."""
     # Arrange
     instruction = (
         'example query: "What is the weather?" example response: "The weather'