quiche build: make check test_tscpputil failure

[bneradt]

The CI quiche make check test fails in the CI branch builds:
https://ci.trafficserver.apache.org/view/10.x-master/job/master/job/quiche/73/execution/node/77/log/

FAIL: test_tscpputil
============================================================================
Testsuite summary for Apache Traffic Server 10.0.0
============================================================================
# TOTAL: 1
# PASS:  0
# SKIP:  0
# XFAIL: 0
# FAIL:  1
# XPASS: 0
# ERROR: 0
============================================================================
See src/tscpp/util/test-suite.log
Please report to dev@trafficserver.apache.org
============================================================================
make[3]: *** [Makefile:1179: test-suite.log] Error 1
make[3]: Leaving directory '/home/jenkins/workspace/master/quiche/src/src/tscpp/util'
make[2]: *** [Makefile:1287: check-TESTS] Error 2
make[2]: Leaving directory '/home/jenkins/workspace/master/quiche/src/src/tscpp/util'
make[1]: *** [Makefile:1361: check-am] Error 2
make[1]: Leaving directory '/home/jenkins/workspace/master/quiche/src/src/tscpp/util'
make: *** [Makefile:897: check-recursive] Error 1

I could not reproduce this locally, despite using the same docker image and build steps that CI uses.

[bneradt]

This was a CI environment issue. We have to set the LD_LIBRARY_PATH for boring:
https://github.com/apache/trafficserver-ci/pull/170/files

For reference, see:
#9679 (comment)