Replace String.replaceAll with substring for better throughput performance

Sometime in the JAX-RS 3.3.x branch, the method org.apache.cxf.jaxrs.utils.JAXRSUtils.combineUriTemplates was introduced. This method calls a costly String.replaceAll in order to remove a '/' character at the end of a uri. This method can perform up to 2% better in throughput scenarios by changing:

return parent.replaceAll("/$", "") + child;

to

return parent.substring(0, parent.length() - 1) + child;