replacePrefixMatch broken in main

[zetaab]

Description:

What issue is being seen? Describe what should be happening instead of
the bug, for example: Envoy should not crash, the expected value isn't
returned, etc.

with envoy gateway 1.1 I was using following spec

    - type: URLRewrite
      urlRewrite:
        path:
          type: ReplacePrefixMatch
          replacePrefixMatch: /docs/

So my goal is to add /docs/ prefix to all url paths. So it will be modified like /docs/<originalpath>.

With latest main the request path was modified only /docs<originalpath> (NOTE! missing last slash)

However, with latest main it will not add the ending slash anymore. I was forced to use

    - type: URLRewrite
      urlRewrite:
        path:
          type: ReplacePrefixMatch
          replacePrefixMatch: /docs//

to get same behaviour working.

Repro steps:

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required to reproduce the bug.

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sharing.

Environment:

Include the environment like gateway version, envoy version and so on.

eg 1.1 (envoy 1.31) and main (with envoy distroless-devel)

Logs:

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[arkodg]

this was supposed to be fixed with #3990