fix: make error msgs of TaskManager more explicit

[hezean]

• What kind of change does this PR introduce? Bug fix

• What is the current behavior? Fixes error msgs of taskmanager client #2013

[codecov]

Codecov Report

Merging #2092 (33d8e5c) into main (b455771) will decrease coverage by 0.01%.
The diff coverage is 0.00%.

@@             Coverage Diff              @@
##               main    #2092      +/-   ##
============================================
- Coverage     75.70%   75.68%   -0.02%     
  Complexity      347      347              
============================================
  Files           615      615              
  Lines        116901   116901              
  Branches       1015     1015              
============================================
- Hits          88499    88477      -22     
- Misses        28193    28215      +22     
  Partials        209      209              

Impacted Files	Coverage Δ
src/client/taskmanager_client.cc	0.00% <0.00%> (ø)
src/sdk/db_sdk.cc	63.45% <0.00%> (-1.13%)	⬇️
src/client/tablet_client.cc	55.14% <0.00%> (-0.45%)	⬇️
src/tablet/tablet_impl.cc	60.04% <0.00%> (-0.25%)	⬇️
src/nameserver/name_server_impl.cc	42.76% <0.00%> (-0.06%)	⬇️
hybridse/src/codec/fe_row_codec.cc	78.64% <0.00%> (+0.15%)	⬆️

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[github-actions]

SDK Test Report

  75 files    75 suites   6m 9s ⏱️
163 tests 161 ✔️ 2 💤 0 ❌
204 runs  202 ✔️ 2 💤 0 ❌

Results for commit 33d8e5c.

[github-actions]

Linux Test Report

       54 files       196 suites   54m 6s ⏱️
  9 008 tests   9 004 ✔️ 4 💤 0 ❌
13 259 runs  13 255 ✔️ 4 💤 0 ❌

Results for commit 33d8e5c.

[tobegit3hub]

LGTM