Add docker major version tag when releasing

[yixinglu]

For releasing each version, action will update the major version tag for each docker image, such as:

v3.0.0 -> v3, latest
v2.6.0 -> v2, latest
v2.5.1 -> v2, latest

[codecov-commenter]

Codecov Report

Merging #2921 (84b5b44) into master (fd2e949) will increase coverage by 0.09%.
The diff coverage is 96.32%.

@@            Coverage Diff             @@
##           master    #2921      +/-   ##
==========================================
+ Coverage   85.45%   85.54%   +0.09%     
==========================================
  Files        1225     1229       +4     
  Lines      109855   110383     +528     
==========================================
+ Hits        93872    94432     +560     
+ Misses      15983    15951      -32     

Impacted Files	Coverage Δ
src/kvstore/EventListener.h	32.22% <0.00%> (-0.19%)	⬇️
src/kvstore/KVEngine.h	100.00% <ø> (ø)
src/kvstore/KVStore.h	66.66% <ø> (ø)
src/kvstore/RocksEngine.h	91.66% <ø> (ø)
src/meta/processors/job/JobDescription.h	100.00% <ø> (ø)
src/meta/processors/job/JobManager.h	100.00% <ø> (ø)
src/mock/AdHocSchemaManager.cpp	56.95% <0.00%> (-0.38%)	⬇️
src/meta/processors/job/AdminJobProcessor.cpp	65.11% <62.50%> (ø)
src/common/function/test/FunctionManagerTest.cpp	98.78% <63.63%> (-0.20%)	⬇️
src/storage/http/StorageHttpPropertyHandler.cpp	78.26% <78.26%> (ø)
... and 78 more

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