Adds migration guides for v1 plugins. Guides added in this PR:
-
[AWS](https://github.com/cloudquery/cloudquery/blob/migration-guides/plugins/source/aws/docs/v1-migration.md)
(Updated)
-
[Azure](https://github.com/cloudquery/cloudquery/blob/migration-guides/plugins/source/azure/docs/v1-migration.md)
-
[Cloudflare](https://github.com/cloudquery/cloudquery/blob/migration-guides/plugins/source/cloudflare/docs/v1-migration.md)
-
[DigitalOcean](https://github.com/cloudquery/cloudquery/blob/migration-guides/plugins/source/digitalocean/docs/v1-migration.md)
-
[GCP](https://github.com/cloudquery/cloudquery/blob/migration-guides/plugins/source/gcp/docs/v1-migration.md)
-
[Github](https://github.com/cloudquery/cloudquery/blob/migration-guides/plugins/source/github/docs/v1-migration.md)
-
[Okta](https://github.com/cloudquery/cloudquery/blob/migration-guides/plugins/source/okta/docs/v1-migration.md)

Heroku was left out because it was never released pre-v1. K8s will be
added when it is ready, and terraform requires some changes to work
(will follow up later today).

Generating these requires a bit of manual setup, but for future
reference, the process I have locally right now can be replicated using
something like this:

```
git worktree add ../v0
git worktree add ../v1
cd ../v0 && git checkout ab65d1e # or any v0 commit
cd ../v1 && make build
cd ..
```

Then run this script from outside the git root:

```
plugins="aws gcp azure cloudflare digitalocean github okta" 

mkdir -p docs/tables-v0
mkdir -p docs/tables-v1
for p in $plugins
do
	echo "Generating migration guide for $p"
	cp -r v0/plugins/source/$p/docs/tables/* docs/tables-v0
	./v1/bin/$p doc docs/tables-v1
	./v1/bin/v1-migration -o cloudquery/plugins/source/$p/docs/v1-migration.md -v1 docs/tables-v0 -v2 docs/tables-v1
done
```