refactor: show tables and show databases

[killme2008]

I hereby agree to the terms of the GreptimeDB CLA.

Refer to a related PR or issue link (optional)

#3354

What's changed and what's your intention?

Main changes:

• Make show tables and show databases to query data from information_schema tables.
• Fixed where clause can't work properly, SHOW FULL TABLES WHERE Table_type != 'VIEW' for example.

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

Attention: Patch coverage is 93.12977% with 9 lines in your changes are missing coverage. Please review.

Project coverage is 84.67%. Comparing base (2a675e0) to head (93fd61f).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3423      +/-   ##
==========================================
- Coverage   85.00%   84.67%   -0.33%     
==========================================
  Files         889      889              
  Lines      146596   146488     -108     
==========================================
- Hits       124613   124044     -569     
- Misses      21983    22444     +461