test: in test-tls-connect replace fixturedir w fixture mod

fixes: code & learn 10.6 vancouver 1st task

Checklist

• [X ] make -j4 test (UNIX), or vcbuild test (Windows) passes
• [ X] tests and/or benchmarks are included
• documentation is changed or added
• [X ] commit message follows commit guidelines

Affected core subsystem(s)

• updated test/test-tls-connect