Fix the link 'guide' in 'Getting started section'
Fix the link 'guide' in 'Getting started section'

The link points to https://github.com/zulip/zulip#contributing-to-zulip. It should be pointing to https://github.com/zulip/zulip#ways-to-contribute.
zulip/zulip.github.io,zulip/zulip.github.io