Remove shell highlighting which isn't supported by our version of jekyll. 
Remove shell highlighting which isn't supported by our version of jekyll. 

Fixes #2587.

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Change-Id: Ieaedd70c6b7561be3765fe41f81e3c3f388f9cc7
Reviewed-on: https://cr.bazel.build/9090
PiperOrigin-RevId: 148466063
MOS_MIGRATED_REVID=148466063

bazelbuild/bazel-website,davidzchen/bazel-website,bazelbuild/bazel-website,davidzchen/bazel-website,davidzchen/bazel-website,davidzchen/bazel-website,bazelbuild/bazel-website