[BEAM-12656] Fix go-licenses build

[lostluck]

Update the go-license container to use go 1.16 instead of go 1.15. Some of go-licenses deps have moved to using the go 1.16 embed and io/fs packages, breaking the rule.

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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	---			---	---	---

See .test-infra/jenkins/README for trigger phrase, status and link of all Jenkins jobs.

GitHub Actions Tests Status (on master branch)

See CI.md for more information about GitHub Actions CI.

[lostluck]

R: @alanmyrvold
CC: @angoenka FYI since this will likely need to be cherry picked into the release to be able to build RCs.

[codecov]

Codecov Report

Merging #15215 (e744ebf) into master (6e54d4c) will decrease coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master   #15215      +/-   ##
==========================================
- Coverage   83.82%   83.82%   -0.01%     
==========================================
  Files         441      441              
  Lines       59711    59706       -5     
==========================================
- Hits        50053    50047       -6     
- Misses       9658     9659       +1     

Impacted Files	Coverage Δ
...on/apache_beam/runners/dataflow/dataflow_runner.py	82.81% <100.00%> (+0.42%)	⬆️
sdks/python/apache_beam/utils/interactive_utils.py	90.24% <0.00%> (-4.88%)	⬇️
...hon/apache_beam/runners/worker/bundle_processor.py	93.26% <0.00%> (-0.38%)	⬇️

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[lostluck]

Monday morning ping.

[emilymye]

LGTM