*: add missing error handling

[JmPotato]

Signed-off-by: JmPotato ghzpotato@gmail.com

What problem does this PR solve?

cherry-pick #2708 #2878 to release-4.0

What is changed and how it works?

Check List

Tests

• Unit test
• Integration test

Release note

• No release note

[rleungx]

LGTM

[lhy1024]

/merge

[ti-srebot]

/run-all-tests

[codecov]

Codecov Report

Merging #2915 into release-4.0 will decrease coverage by 0.44%.
The diff coverage is 77.77%.

@@               Coverage Diff               @@
##           release-4.0    #2915      +/-   ##
===============================================
- Coverage        77.82%   77.38%   -0.45%     
===============================================
  Files              210      210              
  Lines            22854    22854              
===============================================
- Hits             17786    17685     -101     
- Misses            3729     3830     +101     
  Partials          1339     1339              

Impacted Files	Coverage Δ
server/tso/tso.go	78.48% <55.55%> (-3.80%)	⬇️
server/schedule/placement/rule_list.go	97.50% <100.00%> (ø)
server/schedule/placement/rule_manager.go	75.32% <100.00%> (ø)
server/statistics/store_collection.go	58.82% <0.00%> (-34.56%)	⬇️
server/region_syncer/server.go	80.55% <0.00%> (-9.73%)	⬇️
server/heartbeat_streams.go	68.00% <0.00%> (-6.00%)	⬇️
server/cluster/cluster.go	80.91% <0.00%> (-2.85%)	⬇️
server/config/persist_options.go	89.76% <0.00%> (-1.58%)	⬇️
server/server.go	76.18% <0.00%> (-1.19%)	⬇️
... and 9 more

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