Del redundant-static-def in cinderx/Jit/codegen/copy_graph.cpp +1

Summary:
LLVM has a warning `-Wdeprecated-redundant-constexpr-static-def` which raises the warning:

> warning: out-of-line definition of constexpr static data member is redundant in C++17 and is deprecated

Since we are now on C++20, we can remove the out-of-line definition of constexpr static data members. This diff does so.

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Reviewed By: meyering

Differential Revision: D78250510

fbshipit-source-id: e5be1a99d118ae327773756e823e28d97542414c

Author: r-barnes

Jit/codegen/copy_graph.cpp

@@ -4,8 +4,6 @@
 
 namespace jit::codegen {
 
-constexpr int CopyGraph::kTempLoc;
-
 CopyGraph::Node::~Node() {
   if (child_node.isLinked()) {
     child_node.Unlink();