fix: set is_time_index properly on updating physical table's schema

[waynexia]

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Closes #3758

What's changed and what's your intention?

Related to this ticket: #2798

Only time_index in schema is set before, but forget to set this on column_schema

Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR does not require documentation updates.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 85.22%. Comparing base (54432df) to head (2033dd8).
Report is 6 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3770      +/-   ##
==========================================
- Coverage   85.55%   85.22%   -0.34%     
==========================================
  Files         945      946       +1     
  Lines      159357   159564     +207     
==========================================
- Hits       136337   135984     -353     
- Misses      23020    23580     +560