feat: automatically adding release notes from changelog

[michael-siek]

Used @stephenmathieson function to add changelog content to Github release for attest-ruby/java/node

Test results attest-java:
https://github.com/dequelabs/attest-java/blob/develop/CHANGELOG.md

Releasing v3.5.1
github-release.v0 release --user  --repo  --tag v3.5.1 --name Release 3.5.1 --description


### Bug Fixes

* IsAuditedForAccessibility should log by default ([#80](https://github.com/dequelabs/attest-java/issues/80)) ([9550f22](https://github.com/dequelabs/attest-java/commit/9550f22))

Test results attest-ruby:
https://github.com/dequelabs/attest-ruby/blob/develop/CHANGELOG.md

Releasing v2.4.0
github-release.v0 release --user  --repo  --tag v2.4.0 --name Release 2.4.0 --description

### Bug Fixes

- not use named capture groups in cucumber step regex ([#60](https://github.com/dequelabs/attest-ruby/issues/60)) ([58f4443](https://github.com/dequelabs/attest-ruby/commit/58f4443))
- Rspec examples test failures ([#47](https://github.com/dequelabs/attest-ruby/issues/47)) ([e0734f2](https://github.com/dequelabs/attest-ruby/commit/e0734f2))

### Features

- update to axe-matchers v2.4.1 ([53a6a2b](https://github.com/dequelabs/attest-ruby/commit/53a6a2b))

Test results attest-node-suite:
https://github.com/dequelabs/attest-node-suite/blob/develop/CHANGELOG.md

Releasing v2.8.1
github-release.v0 release --user  --repo  --tag v2.8.1 --name Release 2.8.1 --description


### Bug Fixes

* **aget:** Enable writing json uri mode ([#331](http://dequelabs/attest-node-suite/issues/331)) ([d3ffc6a](http://dequelabs/attest-node-suite/commits/d3ffc6a))
* **aget:** stub util test properly to allow for cross platform testing ([#280](http://dequelabs/attest-node-suite/issues/280)) ([8dd851b](http://dequelabs/attest-node-suite/commits/8dd851b))
* **aget:** Support Node v8 ([#264](http://dequelabs/attest-node-suite/issues/264)) ([da94013](http://dequelabs/attest-node-suite/commits/da94013))
* **attest-standards:** Allow from a dynamic list of tags ([#295](http://dequelabs/attest-node-suite/issues/295)) ([e885721](http://dequelabs/attest-node-suite/commits/e885721))

Closes issue: https://github.com/dequelabs/HTMLToolsTeamHub/issues/70

Reviewer checks

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• Follows the commit message policy, appropriate for next version
• Has documentation updated, a DU ticket, or requires no documentation change
• Includes new tests, or was unnecessary
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[stephenmathieson]

Few small things.

resolved

resolved

resolved

[stephenmathieson]

This errors if the file does not already exist. See #13

[stephenmathieson]

The Java script has been tested/verified manually. See https://github.com/dequelabs/testing-repo/releases/tag/v3.5.1

[schne324]

Code LGTM... I have one comment (below) but I assume you've thought of this and I'm probably missing something so I am approving 😄

I have 0 experience working with/in this repo, plus I'm no shell script expert so I could be missing something but it seems we could extract the get_changelog() function into it's own file (say get_changelog.sh) and "import" it in each script via source get_changelog.sh.

NOTE: get_changelog.sh needs to be in one of the directories in $PATH; if it's not, you'll need to specify an absolute path

[stephenmathieson]

seems we could extract the get_changelog() function into it's own file

Yep, that would be ideal, but it would be a breaking change, as we'd have to update all of our CI configurations to fetch that file as well. We figured a little copypasta here was better than updating all 12,000,062 repositories.