fix: install curl, gpg, ca-certificates in molecule prepare

The geerlingguy Docker containers don't include curl or gpg, which
are needed by the rootless Docker role to download and dearmor the
Docker APT repository GPG key. Added these prerequisites to the
molecule common prepare playbook.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

ansible/roles/gitea-runner/molecule/common/prepare.yml

@@ -9,9 +9,13 @@
         cache_valid_time: 0
       when: ansible_facts['os_family'] == 'Debian'
 
-    - name: Install python3-debian for deb822_repository module
+    - name: Install prerequisites for rootless Docker role (Debian/Ubuntu)
       ansible.builtin.apt:
-        name: python3-debian
+        name:
+          - curl
+          - gpg
+          - python3-debian
+          - ca-certificates
         state: present
       when: ansible_facts['os_family'] == 'Debian'
 
@@ -19,3 +23,12 @@
       community.general.pacman:
         update_cache: true
       when: ansible_facts['os_family'] == 'Archlinux'
+
+    - name: Install prerequisites for rootless Docker role (Arch Linux)
+      community.general.pacman:
+        name:
+          - curl
+          - gpg
+          - ca-certificates
+        state: present
+      when: ansible_facts['os_family'] == 'Archlinux'