Fix incorrect template instantiation in inline_task_context (#2012) (#2013)

* Fix incorrect template instantiation in inline_task_context (#2012)

Author: SamGaaWaa

include/exec/task.hpp

@@ -117,12 +117,15 @@ namespace experimental::execution
       template <class _ParentPromise>
       constexpr explicit __default_task_context_impl(_ParentPromise& __parent) noexcept
       {
-        if constexpr (__with_affinity && __parent_promise_has_start_scheduler<_ParentPromise>())
+        if constexpr (__with_affinity)
         {
-          // get_start_scheduler is used here to get the parent's "current" scheduler,
-          // which is the one on which this task has been started (i.e., co_await-ed).
-          auto __parent_sched = get_start_scheduler(get_env(__parent));
-          this->__scheduler_  = __parent_sched;
+          if constexpr (__parent_promise_has_start_scheduler<_ParentPromise>())
+          {
+            // get_start_scheduler is used here to get the parent's "current" scheduler,
+            // which is the one on which this task has been started (i.e., co_await-ed).
+            auto __parent_sched = get_start_scheduler(get_env(__parent));
+            this->__scheduler_  = __parent_sched;
+          }
         }
       }