SUBMARINE-1348. Fix implicit Optional check style issues for mypy

[JackLiu00521]

What is this PR for?

Fix mypy python check error (cause by mypy recent change: --no-implicit-optional by default) https://mypy-lang.blogspot.com/2022/11/mypy-0990-released.html

What type of PR is it?

[Bug Fix]

What is the Jira issue?

https://issues.apache.org/jira/browse/SUBMARINE-1348

How should this be tested?

Python check style test will now pass

Screenshots (if appropriate)

Questions:

• Do the license files need updating? No
• Are there breaking changes for older versions? No
• Does this need new documentation? No

[codecov[bot]]

Codecov Report

Merging #1016 (cf187dc) into master (dd6a292) will increase coverage by 53.11%. The diff coverage is 100.00%.

@@              Coverage Diff              @@
##             master    #1016       +/-   ##
=============================================
+ Coverage     22.71%   75.83%   +53.11%     
=============================================
  Files           358      112      -246     
  Lines         29088     4945    -24143     
  Branches       3479        0     -3479     
=============================================
- Hits           6608     3750     -2858     
+ Misses        22266     1195    -21071     
+ Partials        214        0      -214     

Flag	Coverage Δ
python-integration	59.59% <100.00%> (+<0.01%)	:arrow_up:
python-unit	52.19% <100.00%> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...e/submarine/store/model_registry/abstract_store.py	71.92% <100.00%> (ø)
...submarine/store/model_registry/sqlalchemy_store.py	97.09% <100.00%> (ø)
...arine-sdk/pysubmarine/submarine/tracking/client.py	86.07% <100.00%> (ø)
...arine-sdk/pysubmarine/submarine/tracking/fluent.py	86.36% <100.00%> (+0.64%)	:arrow_up:
...atabase/workbench/service/ProjectFilesService.java
...e/submarine/server/rest/workbench/TeamRestApi.java
...ver/submitter/k8s/parser/ExperimentSpecParser.java
...marine/server/submitter/k8s/model/tfjob/TFJob.java
...g/apache/submarine/server/api/experiment/Info.java
...apache/submarine/server/api/spec/NotebookSpec.java
... and 285 more

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