fix: add tailing separator to prefix

[waynexia]

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Refer to a related PR or issue link (optional)

What's changed and what's your intention?

add tailing separator to prefix, otherwise it cannot handle when one schema name is a substring of another.

Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR requires documentation updates.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 85.05%. Comparing base (0575108) to head (dc83970).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4078      +/-   ##
==========================================
- Coverage   85.35%   85.05%   -0.31%     
==========================================
  Files         987      987              
  Lines      172119   172141      +22     
==========================================
- Hits       146908   146409     -499     
- Misses      25211    25732     +521     

[fengjiachun]

LGTM