Add support for GA v4

What's Changed

• Bump phpseclib/phpseclib from 3.0.14 to 3.0.19 in /src by @dependabot in #167
• Bump guzzlehttp/psr7 from 2.3.0 to 2.5.0 in /src by @dependabot in #168
• Add Support for Google Analytics v4 by @cristianuibar in #169

Full Changelog: v4.0.10...v4.1