docs: add missing backslash to bash commands

[kdnakt]

Issue #, if available:

Description of changes:

Description of how you validated changes:

Checklist:

• Write/update tests
• make pr passes
• Update documentation
• Verify transformed template deploys and application functions as expected
• Add/update example to examples/2016-10-31

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

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@@            Coverage Diff             @@
##             develop    #1023   +/-   ##
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  Coverage           ?   94.81%           
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  Files              ?       69           
  Lines              ?     3240           
  Branches           ?      631           
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  Hits               ?     3072           
  Misses             ?       87           
  Partials           ?       81

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