PREUPLOAD.cfg to run crate tool.

Change-Id: I3fe0a8602ef756081052d4beefe25623975ff863
Test: treehugger
Bug: 339424309
diff --git a/PREUPLOAD.cfg b/PREUPLOAD.cfg
new file mode 100644
index 0000000..d31a717
--- /dev/null
+++ b/PREUPLOAD.cfg
@@ -0,0 +1,2 @@
+[Hook Scripts]
+check = cargo run --bin crate_health --manifest-path ../../../development/tools/external_crates/Cargo.toml -- preupload-check ${PREUPLOAD_FILES}