Update tag to ExecutionModel

[ericwudayi]

Describe your changes

Enable users to add tags to their existing execution. It can perform the execution update operation directly through an HTTP PUT request. The detailed example are shown in screenshot using postman.

1. Add add_tag in ExecutionUpdateRequest (flyteidl/protos/admin/execution.proto).
2. Implement add tag details in flyteadmin.
3. Adding test for UpdateExecutionModel and UpdateExecutionModelAddTag

pyflyte run --tag abc --tag tags1 --remote example.py training_workflow --hyperparameters '{"C": 0.1}'
//Go to http://localhost:30080/console/projects/flytesnacks/domains/development/executions/f5300f7f411674b89998 to see execution in the console.

## Put request, adding tags2 into the workflow
curl -X PUT -H "Content-Type: application/json" -d '{"add_tags": ["tags2"]}' http://localhost:30080/api/v1/executions/flytesnacks/development/f5300f7f411674b89998

Check all the applicable boxes

• I updated the documentation accordingly.
• All new and existing tests passed.
• All commits are signed-off.

Screenshots

Initialization:

After PUT Request: (curl -X PUT -H "Content-Type: application/json" -d '{"add_tags": ["tags2"]}' ...)

##ScreentShot in Database
Create the corresponding identity in admin tag DB table

The corresponding execution admin tags DB table

##Tracking PR
#4142

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[codecov]

Codecov Report

Attention: 6 lines in your changes are missing coverage. Please review.

Comparison is base (2edc3bd) 59.52% compared to head (5d07c5f) 59.98%.
Report is 9 commits behind head on master.

❗ Current head 5d07c5f differs from pull request most recent head d23227e. Consider uploading reports for the commit d23227e to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4185      +/-   ##
==========================================
+ Coverage   59.52%   59.98%   +0.46%     
==========================================
  Files         639      570      -69     
  Lines       54611    41225   -13386     
==========================================
- Hits        32506    24728    -7778     
+ Misses      19543    14098    -5445     
+ Partials     2562     2399     -163     

Flag	Coverage Δ
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Files	Coverage Δ
flyteadmin/pkg/manager/impl/execution_manager.go	72.92% <0.00%> (+2.39%)	⬆️
...teadmin/pkg/repositories/transformers/execution.go	83.70% <81.81%> (+2.35%)	⬆️

... and 574 files with indirect coverage changes

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