new: Add account_availability_list module

[yec-akamai]

📝 Description

Add a new list module account_availability_list to show a list of region availabilities to the account. This module is currently not filterable because the API doesn't support filtering.

✔️ How to Test

To test again Alpha, you probably need to overwrite the following variables:

TEST_API_URL=alpha/api-url
TEST_API_CA=your-local-ca-file
LINODE_TOKEN=alpha-linode-token

make TEST_ARGS="-v account_availability_list" test

[zliang-akamai]

Tested and worked well on my end!