[CI] Show PCRE_VERSION, refs 3848

[mwjames]

This PR is made in reference to: #3848

This PR addresses or contains:

This PR includes:

• Tests (unit/integration)
• CI build passed

Fixes #

[mwjames]

To find the used version, look for PCRE in the output [0]:

> php ../../tests/phpunit/phpunit.php -c phpunit.xml.dist
Using PHP 7.1.11

Semantic MediaWiki: 3.2.0-alpha, git: 7d905dc
                    SMWSQLStore (mysql:5.6.33-0ubuntu0.14.04.1)

MediaWiki:          1.32.6, git: 5807cdf (refs/heads/REL1_32)
                    Extension vendor autoloader

Site language:      en
Execution time:     2020-02-22 04:49

Debug logs:         Disabled
Xdebug:             Disabled (or not installed)

Intl/ICU:           1.1.0 / 52.1
PCRE:               8.38 2015-11-23

PHPUnit 6.5.14 by Sebastian Bergmann and contributors.

Runtime:       PHP 7.1.11
Configuration: /home/travis/build/SemanticMediaWiki/mw/extensions/SemanticMediaWiki/phpunit.xml.dist

.............................................................   61 / 8338 (  0%)

[0] https://travis-ci.org/SemanticMediaWiki/SemanticMediaWiki/jobs/653733961