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##### SUMMARY
<!--- Explain the problem briefly below, add suggestions to wording or structure -->
The contains attribute of the find_module has type "string" but is described as "one or more regex patterns". Given that a string can only be one regex pattern (albeit with alternations in it to match against multiple patterns) it is deceptively easy to misread this and try to specify a list of strings as the value of the contains attribute.

Granted, Ansible warns about this when running, but it would be even better to prevent the mistake in the first place.

<!--- HINT: Did you know the documentation has an "Edit on GitHub" link on every page ? -->
I would edit the documentation myself, but I don't actually know what the intended semantics for this are. Is the command meant to take a list of regexes? If so, the bug is that it doesn't. If it's only meant to take a single regex, the bug is in the description in the documentation!

##### ISSUE TYPE
- Documentation Report

##### COMPONENT NAME
<!--- Write the short name of the rst file, module, plugin, task or feature below, use your best guess if unsure -->
find_module

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.8.4
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below
DEFAULT_VAULT_PASSWORD_FILE(env: ANSIBLE_VAULT_PASSWORD_FILE) = /home/kqr/.vaultpass
```

##### OS / ENVIRONMENT
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All (documentation published on the web)

##### ADDITIONAL INFORMATION
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- You can choose seconds, minutes, hours, days, or weeks by specifying the
              first letter of any of those words (e.g., "1w").
        type: str
    patterns:
        default: '*'
        description:
            - One or more (shell or regex) patterns, which type is controlled by C(use_regex) option.
            - The patterns restrict the list of files to be returned to those whose basenames match at
              least one of the patterns specified. Multiple patterns can be specified using a list.
            - The pattern is matched against the file base name, excluding the directory.
            - When using regexen, the pattern MUST match the ENTIRE file name, not just parts of it. So
              if you are looking to match all files ending in .default, you'd need to use '.*\.default'
              as a regexp and not just '\.default'.
            - This parameter expects a list, which can be either comma separated or YAML. If any of the
              patterns contain a comma, make sure to put them in a list to avoid splitting the patterns
              in undesirable ways.
        type: list
        aliases: [ pattern ]
    excludes:
        description:
            - One or more (shell or regex) patterns, which type is controlled by C(use_regex) option.
            - Items whose basenames match an C(excludes) pattern are culled from C(patterns) matches.
              Multiple patterns can be specified using a list.
        type: list
        aliases: [ exclude ]
        version_added: "2.5"
    contains:
        description:
            - One or more regex patterns which should be matched against the file content.
        type: str