Fix DataCoord panics if message queue service quits before it

[congqixia]

Related #15659

/kind bug

Signed-off-by: Congqi Xia congqi.xia@zilliz.com

[sre-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: congqixia

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• internal/datacoord/OWNERS [congqixia]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[mergify]

@congqixia ut workflow job failed, comment rerun ut can trigger the job again.

[codecov]

Codecov Report

Merging #15702 (789780d) into master (b196029) will decrease coverage by 0.05%.
The diff coverage is 84.61%.

@@            Coverage Diff             @@
##           master   #15702      +/-   ##
==========================================
- Coverage   80.19%   80.14%   -0.06%     
==========================================
  Files         381      381              
  Lines       58407    58398       -9     
==========================================
- Hits        46840    46801      -39     
- Misses       9285     9305      +20     
- Partials     2282     2292      +10     

Impacted Files	Coverage Δ
internal/datacoord/server.go	73.83% <84.61%> (+1.00%)	⬆️
...nternal/querynode/flow_graph_filter_delete_node.go	82.89% <0.00%> (-9.22%)	⬇️
internal/querynode/flow_graph_delete_node.go	81.25% <0.00%> (-7.30%)	⬇️
...nternal/util/rocksmq/client/rocksmq/client_impl.go	75.63% <0.00%> (-4.21%)	⬇️
internal/datacoord/segment_manager.go	81.78% <0.00%> (-1.04%)	⬇️
internal/querycoord/task_scheduler.go	74.22% <0.00%> (-0.96%)	⬇️
internal/querynode/query_collection.go	80.98% <0.00%> (-0.86%)	⬇️
internal/core/src/query/Parser.cpp	91.37% <0.00%> (-0.84%)	⬇️
internal/querycoord/task.go	79.44% <0.00%> (-0.50%)	⬇️
internal/querycoord/meta.go	81.73% <0.00%> (-0.40%)	⬇️
... and 12 more

[sunby]

/lgtm