fix: Resolve issue that causes make unittest and make install to fail

[lgarber-akamai]

📝 Description

This change resolves two issues that caused the make unittest and make install targets to fail on certain machines:

• The PyTest Ansible plugin (pytest-ansible) package was being explicitly installed but is now provided directly in the ansible package, causing a conflict.
• The collections symlink was not being ignored in the galaxy.yml file, leading to an error when attempting to resolve the link during install
  • Unexpected Exception, this is probably a bug: "linkname 'collections/ansible_collections/linode/cloud/../../../../Makefile' not found"

✔️ How to Test

1. Clone a fresh copy of this PR.

mkdir -p testproject/ansible_collections/linode
cd testproject/ansible_collections/linode
git clone --branch fix/install-unit-test-errors git@github.com:lgarber-akamai/ansible_linode.git cloud
cd cloud

2. Install the project dependencies.

make deps

3. Attempt to run unit tests on the collection.

make unittest

4. Attempt to install the collection.

make install

5. Observe that none of the previous steps failed.