Do not base synchronize source on the inventory directory

Fixes #7366
Update ssh.py

Convert to string to fix runtime error due to string concat in self.common_args += ["-o", "User="+self.user] when ansible_ssh_user is numeric
Fix missing variable initialization so an unspecified internal_network runs
Merge branch 'marcore-devel' into devel
Merge pull request #7380 from carsongee/cg/quantum_ip_subnet

Fix missing variable initialization so an unspecified internal_network works
Merge pull request #7382 from jimi-c/issue_7366_synchronize_inventory_dir

Do not base synchronize source on the inventory directory
Use utils.combine_vars on vars_files data

Fixes #7345
Correctly cast the size_gb value for vpshere disks

Fixes #7385