Fix //scouting/deploy

The deployed binary currently prints the following error:

    ERROR: cannot find bazel_tools/tools/bash/runfiles/runfiles.bash

This is a side effect of Iaac8b3fbe76182859962e0d60a68fe3de0fe34cb
which started using the runfiles API. The final deployed binary did
not have the same runfiles layout. The `pkg_tar` rule unfortunately
does not recreate the same runfiles tree. The workaround here is to
fake it with some symlinks.

The scouting server starts up again.

Signed-off-by: Philipp Schrader <philipp.schrader@gmail.com>
Change-Id: I8312dfd88d1c37223885a115dbe0b6d006d1e802
diff --git a/scouting/deploy/scouting.service b/scouting/deploy/scouting.service
index b22a57d..5aa64b0 100644
--- a/scouting/deploy/scouting.service
+++ b/scouting/deploy/scouting.service
@@ -7,6 +7,7 @@
 Group=www-data
 Type=simple
 WorkingDirectory=/opt/frc971/scouting_server
+Environment=RUNFILES_DIR=/opt/frc971/scouting_server
 ExecStart=/opt/frc971/scouting_server/scouting/scouting \
     -port 8080 \
     -db_config /var/frc971/scouting/db_config.json \