UNDERTOW-1565 Don't encode query strings and URI paths while redirecting

[jaikiran]

The commit here fixes the issue reported in https://issues.jboss.org/browse/UNDERTOW-1565

The code in SinglePortConfidentialityHandler which deals with forming the redirect URI was using the 7 argument constructor of java.net.URI, which as per its javadoc, internally encodes the passed parameters, like the queryString. We do not want that to happen, since the query string and other components of the URI that we are building aren't expected to be decoded/encoded, by the container, while we are building the redirect URI.

The commit here uses a StringBuilder to form the redirect URI and then passes it to the single argument constructor of java.net.URI which doesn't do the encoding of the passed parameter, unlike the 7 argument constructor.

The commit also includes an update to an existing testcase to reproduce the issue and verify the fix.

[jaikiran]

retest this please

[jaikiran]

These failures don't look related to this change (and in fact the tests work fine locally)