DOC Add missing quote on route example

[catharsisjelly]

Description

Found a missing quote in the documentation for routing

Issues

• Missing Quote on Route example #611

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[catharsisjelly]

After reading the instructions I was not sure if I need to target 5.3 for this or not. I'm happy to rebase the change to 5.3 if needed

[GuySartorelli]

Yes, please retarget this PR to 5.3 - otherwise the changes won't be seen until April.

[catharsisjelly]

Somehow I messed this up and it auto-merged after I rebased I'll resubmit the change