Only use `chr(30)` and `chr(31)` delimiters in cirq-ionq

[splch]

• [x] update tests to remove\u* and \x*

relates to #5216

[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 99.38%. Comparing base (8dd8a8f) to head (01c892c).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7699      +/-   ##
==========================================
- Coverage   99.38%   99.38%   -0.01%     
==========================================
  Files        1090     1090              
  Lines       98300    98301       +1     
==========================================
  Hits        97695    97695              
- Misses        605      606       +1     

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[mhucka]

@splch Thank you for your work on this! When you get a chance, could you update the title of this PR to mention that this is for cirq-ionq, and also add a bit more explanation to the PR description? This will help future contributors and maintainers when reading and searching through past work.

[mhucka]

@splch I'm not sure if this draft PR is still something planned. It looks like the associated issue was closed. Maybe this should be closed too? (No biggie either way; just going around and checking up on things.)