Bad link in examples.rst in Agent Runtime SDK Examples section

[arleyl]

Bad link on https://github.com/cisco-ai-defense/ai-defense-python-sdk/blob/main/docs/source/examples.rst
in "See the agentsec examples README".

Replace it with the correct URL,
https://github.com/cisco-ai-defense/ai-defense-python-sdk/tree/main/examples/agentsec