Templating broken by errant unset statement

[sosherof]

At the end of Requests->send() is an unset statement that kills the curl handle property ($this->_ch). This throws a warning in PHP 8.x. See PR for fix.

[sosherof]

I see now that this is related to issue #227 (PR #229 ). I think the correct action is to set the _ch object to null so it'll be GC'd and can be reset during the next send operations. Using unset removes the property from the Request object instance and PHP 8 doesn't allow dynamic property creation so the subsequent call to _curlPrep() at the top of send() throws an error.

See PR #306