publish develop snapshots on every commit to develop

[hellochar]

Fixes #3308

Note: With our current release process, the following behavior happens:

1. We commit a "bump version release" for e.g. v3.2.0, which triggers a dev snapshot
2. That commit will get published as e.g. 3.1.0-6-g123abc to next
3. Then, we create git tag v3.2.0, and publish 3.2.0 to latest (which is actually the exact same release as 3.1.0-6g123abc).

This means every latest release will be mirrored as a next release with a different version number, which is not ideal. Thoughts? @themadcreator @giladgray @aidanns

Also, on the next commit to develop, we'd publish 3.2.0-1-g-456def to next -- this means next never gets 3.2.0; they just jump from 3.1.0-6 to 3.2.0.

[adidahiya]

This means every latest release will be mirrored as a next release with a different version number, which is not ideal.

This sounds totally fine. Multiple releases off the same commit, as long as they all adhere to semver and are predictable, are fine.