Add a lock to protect the coordinator to avoid data race condtions.

[sighingnow]

What do these changes do?

It's looks not striaghtfoward for add concurrent support in coordinator and grape-engine, thus we choose to force the requests come one-by-one.

Related issue number

N/A

[codecov-commenter]

Codecov Report

Merging #1445 (c81afc6) into main (8af17df) will decrease coverage by 0.88%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #1445      +/-   ##
==========================================
- Coverage   74.66%   73.77%   -0.89%     
==========================================
  Files          88       88              
  Lines        9675     9679       +4     
==========================================
- Hits         7224     7141      -83     
- Misses       2451     2538      +87     

Impacted Files	Coverage Δ
python/graphscope/client/session.py	75.04% <100.00%> (-0.01%)	⬇️
...ope/analytical/app/average_shortest_path_length.py	77.77% <0.00%> (-22.23%)	⬇️
python/graphscope/framework/dag_utils.py	63.07% <0.00%> (-15.69%)	⬇️
python/graphscope/analytical/app/clustering.py	90.00% <0.00%> (-10.00%)	⬇️
python/graphscope/framework/graph_schema.py	62.58% <0.00%> (-5.76%)	⬇️
python/graphscope/framework/utils.py	66.84% <0.00%> (-2.62%)	⬇️
python/graphscope/framework/operation.py	86.11% <0.00%> (-1.39%)	⬇️

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