fix: add PHP 8.4 compatibility to last release compatible with PHP 7.4

[bshaffer]

Ensures that the last google/auth release which was compatible with PHP 7.4 will be compatible with PHP 8.4 as well.

Once this is merged, we will tag this as v1.37.2

fixes #590

[mikkamp]

Thanks @bshaffer
We've tested using these branches with our extension in woocommerce/google-listings-and-ads#2714
Everything looks good and we no longer receive deprecation notices from this package.

[bshaffer]

@mikkamp thanks for your review! I've tagged v1.37.2 with these changes, so this should be good to go.