Fix for index out of bounds exception keycloak 25 issue 214

[jbentley6]

should fix IndexOutOfBoundsException with keycloak 25

Motivation

aerogear#214

What

Adding a check that matchedURIs is not an empty list to ResourceExtractor.getURI

Why

Currently when using version keycloak-metrics-spi-6.0.0.jar with Keycloak 25 when a call comes into a URI that doesn't have a matching resource uriInfo.getMatchedURIs returns an empty list see https://jakarta.ee/specifications/platform/9/apidocs/jakarta/ws/rs/core/uriinfo#getMatchedURIs--

How

Adding a check to ensure that get(0) is not called on the empty list

Verification Steps

Add the steps required to check this change. Following an example.

1. Go to XX >> YY >> SS
2. Create a new item N with the info X
3. Try to edit this item
4. Check if in the left menu the feature X is not so long present.

Checklist:

• Code has been tested locally by PR requester
• Changes have been successfully verified by another team member

Progress

• Finished task
• TODO

Additional Notes

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