[BEAM-10771] Fix whitespace error causing whitespace lint to fail

[lukecwik]

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Post-Commit Tests Status (on master branch)

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

Pre-Commit Tests Status (on master branch)

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

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GitHub Actions Tests Status (on master branch)

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[lukecwik]

The current whitespace lint that was added as part of #12444 is failing.

R: @pabloem@kevingg

[robertwb]

LGTM