add virtualenv to playground CD

[volatilemolotov]

Adds virtualenv to bypass the new debian pip requirement of using system packages. Given that requirements.txt is used pip is easier to handle. This was chosen instead of --break-system-packages switch for pip as i could not see if it would cause issues elsewhere.

Also bumps PyYAML to 6.0.2 because of some issue with cython.

Should help with #32544

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[Abacn]

thank you!

[volatilemolotov]

@Abacn i have also triggered manual jobs for examples. Both prod and dev