Fix path for collect_bazel_targets.py
Fix path for collect_bazel_targets.py

Summary: changes can't find collect_bazel_targets.py

Test Plan: tested locally by running from different directories

Reviewers: anupc

Reviewed By: anupc

Subscribers: changesbot, kylec

Differential Revision: https://tails.corp.dropbox.com/D212227

dropbox/changes,dropbox/changes,dropbox/changes,dropbox/changes