fix: phpseclib security vulnerability

[yoeriboven]

Upgrades phpseclib to the patched version 3.0.34

GHSA-jpr7-q523-hx25

[google-cla]

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[conventional-commit-lint-gcf]

🤖 I detect that the PR title and the commit message differ and there's only one commit. To use the PR title for the commit history, you can use Github's automerge feature with squashing, or use automerge label. Good luck human!

-- conventional-commit-lint bot
https://conventionalcommits.org/

[bshaffer]

@yoeriboven please sign the google SLA so I can merge this pull request!

[yoeriboven]

@bshaffer Done!