Make url by value in Request

There's some tough-to-track-down safety problems in http Request.  This
commit is an attempt to make things more safe, even if it isn't clear
how the old code was wrong.

Previously, the old code took a url_view from the target() string for a
given URI.  This was effectively a pointer, and needed to be updated in
custom move/copy constructors that were error prone to write.

This commit moves to taking the URI by non-view, which involves a copy,
but allows us to use the default move and copy constructors, as well as
have no internal references within Request, which should improve the
safety and reviewability.

There's already so many string copies in bmcweb, that this is unlikely
to show up as any sort of performance regression, and simple code is
much better in this case.

Note, because of a bug in boost::url, we have to explicitly construct a
url_view in any case where we want to use segments() or query() on a
const Request.  This has been reported to the boost maintainers, and is
being worked for a long term solution.

https://github.com/boostorg/url/pull/704

Tested: Redfish service validator passed on last commit in series.

Signed-off-by: Ed Tanous <edtanous@google.com>
Change-Id: I49a7710e642dff624d578ec1dde088428f284627
diff --git a/redfish-core/lib/task.hpp b/redfish-core/lib/task.hpp
index 2e7481a..4edfe18 100644
--- a/redfish-core/lib/task.hpp
+++ b/redfish-core/lib/task.hpp
@@ -47,7 +47,7 @@
 struct Payload
 {
     explicit Payload(const crow::Request& req) :
-        targetUri(req.url), httpOperation(req.methodString()),
+        targetUri(req.url().encoded_path()), httpOperation(req.methodString()),
         httpHeaders(nlohmann::json::array())
     {
         using field_ns = boost::beast::http::field;