Fix ParseError within PHPUnit

[giggsey]

The old version of PHP-VCR (~4 years) was causing a syntax error within PHPUnit.

Instead, don't use the fork anymore, and allow for more up-to-date versions.

Composer changes:

• Upgrading beberlei/assert (v2.9.9 => v3.3.2)
• Downgrading php-vcr/php-vcr (dev-master fed758e => 1.5.2)
• Locking psr/event-dispatcher (1.0.0)
• Upgrading symfony/deprecation-contracts (v2.5.1 => v2.5.2)
• Upgrading symfony/event-dispatcher (v4.4.37 => v5.4.9)
• Upgrading symfony/event-dispatcher-contracts (v1.1.12 => v2.5.2)
• Upgrading symfony/polyfill-ctype (v1.25.0 => v1.26.0)
• Upgrading symfony/polyfill-php80 (v1.25.0 => v1.26.0)
• Upgrading symfony/yaml (v4.4.37 => v5.4.10)

[edolix]

Looks great @giggsey ! Thank you so much 🎉