[infra] Copy llvm-strip to shards.

Change-Id: I1a2a8b68c33dd1e3b0071fd1becdeebab3e8a6df
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/294441
Reviewed-by: Siva Annamalai <asiva@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
diff --git a/tools/bots/test_matrix.json b/tools/bots/test_matrix.json
index f2478a0..17a63c8 100644
--- a/tools/bots/test_matrix.json
+++ b/tools/bots/test_matrix.json
@@ -219,8 +219,11 @@
       "pkg/",
       "samples/",
       "tools/",
+      "buildtools/linux-x64/clang/bin/llvm-strip",
       "buildtools/linux-x64/clang/bin/llvm-symbolizer",
+      "buildtools/mac-x64/clang/bin/llvm-strip",
       "buildtools/mac-x64/clang/bin/llvm-symbolizer",
+      "buildtools/win-x64/clang/bin/llvm-strip.exe",
       "buildtools/win-x64/clang/bin/llvm-symbolizer.exe",
       "third_party/android_tools/sdk/platform-tools/adb",
       "third_party/android_tools/ndk/toolchains/aarch64-linux-android-4.9/prebuilt/linux-x86_64/bin/aarch64-linux-android-strip",