Remove unneeded (and confusing) .html extension from a couple links in google.github.io/closure-library documentation.
Remove unneeded (and confusing) .html extension from a couple links in google.github.io/closure-library documentation.

RELNOTES: n/a

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=254111237

lucidsoftware/closure-library,lucidsoftware/closure-library,lucidsoftware/closure-library,google/closure-library,google/closure-library,google/closure-library,lucidsoftware/closure-library,google/closure-library,google/closure-library