Enhance sast-rule python/eval/rule-eval.yml

Problem

• Add pattern-not for constant strings
• Add other pattern-nots to reduce FPs if applicable.

Solution

Follow the enhance rule checklist.

• Add a runnable test case demonstrating the vulnerability in one of the real world test projects
  • Add a comment above each method/sink of which rule the test was implemented for.
• Fix/update rule to the specification in this issue
• Create a test in the same directory, replacing 'rule-XXX.yml' with 'rule-XXX.java'
  • If one exists, add the variants or update tests for both true and negative cases. Be sure they follow Semgrep's rule testing guidelines.
• Update the CHANGELOG.md with the change
• Push the changes as a feature branch to this repository if access, otherwise to a fork
• Create the MR
• Update the ! in the CHANGELOG.md if necessary after the MR is created
• Assign for review to someone in the CODEOWNERS file