Backport of server: Ensure trigger names are valid paths into release/0.11.x

[hc-github-team-waypoint]

Backport

This PR is auto-generated from #4660 to be assessed for backporting due to the inclusion of the label backport/0.11.x.

The below text is copied from the body of the original PR.

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Prior to this commit, a user could create a bad HTTP path with a trigger name like ../bad. This commit fixes that behavior by validating the given trigger name matches our expected valid path tokens.

With this fix:

brian@ubuntu:waypoint-tetris λ waypoint trigger create -name=../hello -op=build                                                                        ±[main]
! trigger: (name: name cannot contain '../'.).

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Overview of commits

• 75ced63 - 361ed11 - c8616b2