Pass by reference in reproducer causes crash (#12257)

This pass by reference should be a pass by value as the crash callback
is invoked after this stack frame is destroyed.

compiler/src/iree/compiler/API2/Internal/Embed.cpp

diff --git a/compiler/src/iree/compiler/API2/Internal/Embed.cpp b/compiler/src/iree/compiler/API2/Internal/Embed.cpp
index 1184e88..dea1149 100644
--- a/compiler/src/iree/compiler/API2/Internal/Embed.cpp
+++ b/compiler/src/iree/compiler/API2/Internal/Embed.cpp
@@ -692,7 +692,7 @@
   };
 
   unwrap(inv)->passManager.enableCrashReproducerGeneration(
-      [&](std::string &errorMessage)
+      [=](std::string &errorMessage)
           -> std::unique_ptr<mlir::PassManager::ReproducerStream> {
         iree_compiler_output_t *output = nullptr;
         auto error = onCrashCallback(&output, userData);