fix: data race in EachDBNodes

[localvar]

There are two data races in EachDBNodes:

• the write of err is a data race and could cause a crash when reading the error.
• the read/write of hasErr is a data race, though I don't think it will cause severe issues, its usage does not make much sense in a concurrent program.

other minor improvements:

• don't log "retry execute command" before timeout
• refactor to EachDBNodes and IsRetryErrorForPtView

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• Test A
• Test B
• Test cases to be added
• No code

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[codecov]

Codecov Report

Attention: Patch coverage is 38.70968% with 19 lines in your changes are missing coverage. Please review.

Project coverage is 74.71%. Comparing base (222f626) to head (735a2c9).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #503   +/-   ##
=======================================
  Coverage   74.71%   74.71%           
=======================================
  Files         558      558           
  Lines      118219   118212    -7     
=======================================
- Hits        88324    88319    -5     
+ Misses      24381    24379    -2     
  Partials     5514     5514           

[xiangyu5632]

@fx408 review required, please

[xiangyu5632]

tks @localvar