Update contributing, changelog, and stale.yml files.

Author: thomashoneyman

.github/workflows/stale.yml

@@ -90,7 +90,7 @@ See the [docs](./docs) for an in-depth overview of the rest of the Argonaut Core
 `argonaut-core` documentation is stored in a few places:
 
 1. Module documentation is [published on Pursuit](https://pursuit.purescript.org/packages/purescript-argonaut-core).
-2. Written documentation and [the changelog](./docs/CHANGELOG.md) are kept in [the docs directory](./docs).
+2. Written documentation is kept in [the docs directory](./docs).
 3. Usage examples can be found in [the test suite](./test).
 
 If you get stuck, there are several ways to get help:
@@ -104,6 +104,6 @@ You can contribute to `argonaut-core` in several ways:
 
 1. If you encounter a problem or have a question, please [open an issue](https://github.com/purescript-contrib/purescript-argonaut-core/issues). We'll do our best to work with you to resolve or answer it.
 
-2. If you would like to contribute code, tests, or documentation, please [read the contributor guide](./.github/CONTRIBUTING.md). It's a short, helpful introduction to contributing to this library, including development instructions.
+2. If you would like to contribute code, tests, or documentation, please [read the contributor guide](./CONTRIBUTING.md). It's a short, helpful introduction to contributing to this library, including development instructions.
 
 3. If you have written a library, tutorial, guide, or other resource based on this package, please share it on the [PureScript Discourse](https://discourse.purescript.org)! Writing libraries and learning resources are a great way to help this library succeed.

.github/CONTRIBUTING.md renamed to CONTRIBUTING.md

@@ -1,6 +1,6 @@
 # Argonaut Core Documentation
 
-This directory contains documentation for `argonaut-core`. If you are interested in contributing new documentation, please read the [contributor guidelines](../.github/CONTRIBUTING.md) and [What Nobody Tells You About Documentation](https://documentation.divio.com) for help getting started.
+This directory contains documentation for `argonaut-core`. If you are interested in contributing new documentation, please read the [contributor guidelines](../CONTRIBUTING.md) and [What Nobody Tells You About Documentation](https://documentation.divio.com) for help getting started.
 
 ## Tutorial