Remove is_buck2() calls from eden/mononoke/tests/integration/facebook…

…/symlink.bzl

Summary:
buck1 is declared dead, is_buck2() checks will always return true. We can statically eliminate
these calls and associated conditional checks. eden/mononoke/tests/integration/facebook/symlink.bzl was codemodded with libcst.

Reviewed By: dtolnay

Differential Revision: D63295816

fbshipit-source-id: a115d2764b868bb5b4d3a27622a0107782500cc3

eden/mononoke/tests/integration/facebook/symlink.bzl

@@ -1,8 +1,6 @@
-load("@fbcode_macros//build_defs:native_rules.bzl", "buck_filegroup")
-load("@fbsource//tools/build_defs/buck2:is_buck2.bzl", "is_buck2")
 load(
     "//eden/mononoke/tests/integration/facebook:symlink_impl.bzl?v2_only",
     "symlink_v2",
 )
 
-symlink = symlink_v2 if is_buck2() else buck_filegroup
+symlink = symlink_v2