DOC Adding missing quote on routing example

[catharsisjelly]

Description

Found a missing quote in the documentation for routing

Issues

• Missing Quote on Route example #611

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[catharsisjelly]

A resubmit of #612 as I messed it up, this is now using the right branch. Let me know if you want any changes.

[GuySartorelli]

Thanks. Minor change - the colon is part of YAML syntax, not part of the string.

[GuySartorelli]

LGTM, thanks again