Update ADOPTERS.md

[mjallday]

Added VGS adoption statement. Related to #776

If a logo is required there are such available at https://www.verygoodsecurity.com/press-and-assets

Happy to take feedback on the usage statement and adjust as we publish more details in the future about how we're integrating.

[derek]

Thank you for your contribution. I've just checked and your commit doesn't appear to be signed-off. That's something we need before your Pull Request can be merged. Please see our contributing guide.
Tip: if you only have one commit so far then run: git commit --amend --signoff and then git push --force.

[alexellis]

LGTM

[alexellis]

Happy to take feedback on the usage statement and adjust as we publish more details in the future about how we're integrating.

Thank you for the PR and I think this is consistent with what other companies have put forward. What I'd be interested in doing is perhaps a segment for use in a blog post or conference talk later on - we could do that over email perhaps?

Thanks again for getting this done.

Alex