[BEAM-12191] Add a test for python template generation with upload_graph

[azurezyq]

Add a test for #14582

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ValidatesRunner compliance status (on master branch)

Lang	ULR	Dataflow	Flink	Samza	Spark	Twister2
Go	---			---		---
Java
Python	---			---		---
XLang				---		---

Examples testing status on various runners

Lang	ULR	Dataflow	Flink	Samza	Spark	Twister2
Go	---	---	---	---	---	---	---
Java	---		---	---	---	---	---
Python	---	---	---	---	---	---	---
XLang	---	---	---	---	---	---	---

Post-Commit SDK/Transform Integration Tests Status (on master branch)

Go	Java	Python

Pre-Commit Tests Status (on master branch)

---	Java	Python	Go	Website	Whitespace	Typescript
Non-portable
Portable	---			---	---	---

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GitHub Actions Tests Status (on master branch)

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[azurezyq]

R: @tvalentyn

[codecov]

Codecov Report

Merging #14600 (cec2099) into master (6cdf356) will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #14600   +/-   ##
=======================================
  Coverage   83.66%   83.67%           
=======================================
  Files         446      446           
  Lines       59239    59251   +12     
=======================================
+ Hits        49564    49579   +15     
+ Misses       9675     9672    -3     

Impacted Files	Coverage Δ
.../interactive/display/interactive_pipeline_graph.py
...m/examples/snippets/transforms/aggregation/mean.py
...ache_beam/runners/interactive/recording_manager.py
...sdks/python/apache_beam/dataframe/partitionings.py
.../python/apache_beam/testing/test_stream_service.py
...srcs/sdks/python/apache_beam/metrics/metricbase.py
...ks/python/apache_beam/runners/worker/sideinputs.py
...g/benchmarks/nexmark/queries/nexmark_query_util.py
...on/apache_beam/portability/api/metrics_pb2_urns.py
...cp/internal/clients/bigquery/bigquery_v2_client.py
... and 882 more

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