Description of problem:
Package perl-Test-Vars fails to build from source in Fedora Rawhide with new Perl 5.38.

+ ./Build test
# Testing Test::Vars/0.015
t/00_load.t .............. ok
t/01_all_vars_ok_self.t .. ok
# Test::Vars ignores CompileError.pm because: Intentional compile error.
# Test::Vars ignores ImplicitTopic.pm because: Can't use global $_ in "my" at t/lib/ImplicitTopic.pm line 6, near "my $_ "
t/02_no_warnings.t ....... ok
t/03_warned.t ............ ok
t/04_ignores.t ........... ok
t/05_test_vars.t ......... ok
t/06_vars_ok_self.t ...... ok
#   Failed test 'got expected output from test_vars'
#   at t/07_stub_sub_bug.t line 25.
#     Structures begin differing at:
#          $got->[0][2][1][1] = '$x is used once in &StubSub::foo '
#     $expected->[0][2][1][1] = '$x is used once in &StubSub::foo at t/lib/StubSub.pm line 13'
# Looks like you failed 1 test of 2.
t/07_stub_sub_bug.t ...... 
Dubious, test returned 1 (wstat 256, 0x100)
Failed 1/2 subtests 
t/08_undef_aux_list.t .... ok
t/09_array_slice.t ....... ok
t/10_my_sub.t ............ ok
Test Summary Report
-------------------
t/07_stub_sub_bug.t    (Wstat: 256 (exited 1) Tests: 2 Failed: 1)
  Failed test:  2
  Non-zero exit status: 1
Files=11, Tests=71,  1 wallclock secs ( 0.04 usr  0.01 sys +  1.14 cusr  0.31 csys =  1.50 CPU)
Result: FAIL

Version-Release number of selected component (if applicable):
0.015-9.fc39

Steps to Reproduce:
koji build --scratch f39 perl-Test-Vars-0.015-9.fc39.src.rpm

Additional info:
This package is tracked by Koschei. See:
https://koschei.fedoraproject.org/package/perl-Test-Vars

Reproducible: Always