exclude eden/scm build artifacts from the getdeps path map

Summary:
If you have built the `eden/scm` subdirectory with `make local` in your
repository it will have left a bunch of build output artifacts in the source
tree.  Update the getdeps shipit path map for eden to explicitly exclude many
of these build artifacts.

In particular:
- Exclude `eden/scm/build/` since this directory can contains a lot of files.
- Exclude all `*.pyc` files since there may be a reasonable number of these.
- Exclude several Cargo-related files since these will cause problems when
  trying to build Rust code.

Reviewed By: chadaustin

Differential Revision: D20570720

fbshipit-source-id: a60dec4854ae470fdb58e9651fd8a3b910c76004

build/fbcode_builder/manifests/eden

@@ -49,6 +49,10 @@ fbcode/tools/lfs = tools/lfs
 ^fbcode/eden/fs/eden-config\.h$
 ^fbcode/eden/hg/.*$
 ^fbcode/eden/mononoke/(?!lfs_protocol)
+^fbcode/eden/scm/build/.*$
+^fbcode/eden/.*/\.cargo/.*$
+/Cargo\.lock$
+\.pyc$
 
 [cmake.defines.all(fb=on,os=windows)]
 INSTALL_PYTHON_LIB=ON