RFR: 8372414: Command "make test-prebuilt" fails when listing tests

[Roman Marchenko]

Restoring a line which, I think, was accidentally removed.

Now the command works OK:

$ JTREG_OPTIONS="-l" TEST=:tier1_part1 make test-prebuilt
...
Tests found: 1,095
Finished running test 'jtreg:test/jdk:tier1_part1'
Test report is stored in build/run-test-prebuilt/test-results/jtreg_test_jdk_tier1_part1

==============================
Test summary
==============================
   TEST                                              TOTAL  PASS  FAIL ERROR  SKIP
>> jtreg:test/jdk:tier1_part1                            1     0     0     1     0 <<
==============================
TEST FAILURE

-------------

Commit messages:
 - 8372414: make test-prebuilt fails when listing tests

Changes: https://git.openjdk.org/jdk/pull/28478/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=28478&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8372414
  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/28478.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28478/head:pull/28478

PR: https://git.openjdk.org/jdk/pull/28478