Add ability to create ssh-keys and provide it to github and gitea

Here we start to have some delicate secrets in the code. Therefore I
need a vault for ansible. This vault contains the tokens to upload
ssh-keys to github and my lovely gitea server.

Note, that this change also adds a `requirements.yml`, this is necessary
because I use the paramater "api_url" of the github_key resource which
was only added in v11, but the debian ansible was shippped with an older
collection.

group_vars/localhost/common.config.yml

@@ -2,3 +2,6 @@ fly_url_linux: https://ci.nehrke.info/api/v1/cli?arch=amd64&platform=linux
 fly_url_darwin: https://ci.nehrke.info/api/v1/cli?arch=amd64&platform=darwin
 fly_url: "{{ fly_url_darwin if ansible_os_family == 'Darwin' else fly_url_linux }}"
 
+gitea_token: "{{ vault_gitea_token }}"
+gitea_api_url: "https://gitea.nehrke.info/api/v1"
+github_token: "{{ vault_github_token }}"