Avoid more test skipping for situations that are actually errors or failures

[johnbillion]

This is a follow-up to #40533.

Some tests contain calls to markTestSkipped() as a result of situations such as incorrect test data or unsuitable test environments. If the test data isn't valid or the environment is not capable of supporting the test then the test should fail, otherwise the tests are not reliable.

[johnbillion]

In 41278:

Build/Test tools: Don't skip tests which rely on OpenSSL when the openssl extension isn't loaded.

See #41676

[johnbillion]

In 41279:

Build/Test tools: Revert [41278] because the PHP 5.2 environment on Travis doesn't support OpenSSL, hence the tests fail.

See #41676

[johnbillion]

Bleugh. This can be reopened if someone wants to fix OpenSSL on PHP 5.2.