Merge branch 'update-multi-get-header' into 'main'

Update multi get header policy.

See merge request gaia-x/data-infrastructure-federation-services/tsa/policies!4

example/getMultiHeaders/1.0/policy.rego

 package example.getMultiHeaders
 
 key = input.headers["X-Cache-Key"]
-host = input.headers["Host"]
+another = input.headers["X-Another-Header"]