v0.30.0

DynamicPPL v0.30.0

Diff since v0.29.2

Merged pull requests:

• Small improvements to probability docs (#675) (@penelopeysm)
• Bump versions of GitHub Actions (#676) (@penelopeysm)
• Bump AbstractPPL to 0.9 (#679) (@penelopeysm)
• Bump codecov/codecov-action from 1 to 4 (#680) (@dependabot[bot])
• Test pre-releases instead of nightly and update actions (#681) (@devmotion)