check_mode should behave pretty similarly to non-check mode -
just don't actually create or delete subnets or change tags.
Using DryRun for check_mode behaves very differently and results
in the following module failure:
```
"msg": "Unable to update tags for subnet-abcd1234,
error: EC2ResponseError: 412 Precondition Failed
<?xml version=\"1.0\" encoding=\"UTF-8\"?>
<Response><Errors><Error><Code>DryRunOperation</Code>
<Message>Request would have succeeded, but DryRun flag
is set.</Message></Error></Errors>
<RequestID>12345678-abcd-1234-abcd-abcd1234abcd</RequestID></Response>"
```
Changes to the metadata format were approved here:
https://github.com/ansible/proposals/issues/54
* Update documentation to the new metadata format
* Changes to metadata-tool to account for new metadata
* Add GPL license header
* Add upgrade subcommand to upgrade metadata version
* Change default metadata to the new format
* Fix exclusion of non-modules from the metadata report
* Fix ansible-doc for new module metadata
* Exclude metadata version from ansible-doc output
* Fix website docs generation for the new metadata
* Update metadata schema in valiate-modules test
* Update the metadata in all modules to the new version
ensure_tags fails if `tags` is None rather than an empty
dict. Ensure that not passing `tags` parameter is equivalent
to passing an empty dict.
Fixes#21778
Ryan Brown
Toshio Kuratomi
Will Thames
Brandon Davidson
Sloane Hertel
Matt Clay
James Cammarata