[exec.snd.expos] Add '\exposid' for exposition-only identifiers in basic-state constructor (#7304)

Author: lewissbaker

source/exec.tex

@@ -1618,8 +1618,8 @@
   template<class Sndr, class Rcvr>
   struct @\exposid{basic-state}@ {                                          // \expos
     @\exposid{basic-state}@(Sndr&& sndr, Rcvr&& rcvr) noexcept(@\seebelow@)
-      : rcvr(std::move(rcvr))
-      , state(@\exposid{impls-for}@<tag_of_t<Sndr>>::@\exposid{get-state}@(std::forward<Sndr>(sndr), rcvr)) { }
+      : @\exposid{rcvr}@(std::move(rcvr))
+      , @\exposid{state}@(@\exposid{impls-for}@<tag_of_t<Sndr>>::@\exposid{get-state}@(std::forward<Sndr>(sndr), @\exposid{rcvr}@)) { }
 
     Rcvr @\exposid{rcvr}@;                                                  // \expos
     @\exposid{state-type}@<Sndr, Rcvr> @\exposid{state}@;                               // \expos