[rset] kill the rset._rqlst cache
Right now it "works" for the standard, internal uses.
However when we will fold ClientConnection and Connection, it will
hurt, because suddenly we get more cache hits, and the following
situation would become commonplace:
* there is an un-annotated _rqlst given by the querier
* some view (e.g. facets) requests the .syntax_tree, which takes a
copy of _rqlst
* the view actually expects the rql syntax tree to be annotated, but
it was not, hence we crash.
Related to #3837233.
[MESSAGES CONTROL]
disable-msg = C0301
[VARIABLES]
# Enable / disable this checker
enable-variables = yes
additional-builtins = _, display_name
[BASIC]
required-attributes=
attr-rgx = (w|[a-z_][a-z0-9_]{2,30})
variable-rgx = (w|[a-z_][a-z0-9_]{2,30})$
argument-rgx = (w|[a-z_][a-z0-9_]{2,30})$
[TYPECHECK]
generated-members=debug,info,notice,warning,error,critical,exception