Revert D93500770: Remove FbsourceRoot and BuckMode dead code

Differential Revision:
D93500770

Original commit changeset: c1213f7e451d

Original Phabricator Diff: D93500770

fbshipit-source-id: febb62af86325ac9d66f01589ff90c15ad415522

Author: brittanyrey

prelude/python/lazy_imports.bzl

@@ -21,6 +21,8 @@ def run_lazy_imports_analyzer(
     cmd = cmd_args(ctx.attrs.lazy_imports_analyzer[RunInfo], hidden = resources)
     cmd.add(dbg_source_db_output)  # First arg: <DB_PATH>
     cmd.add(output.as_output())  # Second arg: <OUTPUT_PATH>
+    cmd.add("--buck_mode")
+    cmd.add("buck-build")
 
     ctx.actions.run(
         cmd,