refactor the search request URI query parameter clean up

[PrasannaHegde1]

Describe the bug Instead of cleaning up existing query parameters in the request URI through String.replace(), We should be building an object that represents the request URI, then rendering that object as a URI string.

Environment Which version of LinuxForHealth FHIR Server? 5.0

To Reproduce Steps to reproduce the behavior:

1. Go to FHIRRestHelper.addLinks()
2. Observe the requestUri.replace() method calls.

Expected behavior We should be building an object that represents the request URI, then rendering that object as a URI string.