[Documentation] [zos_data_set] Update member doc to explain what type of member is created

[ddimatos]

Documentation issue description

The zos_data_set with MEMBER option creates a member, there is no indication of what type of member is created, looking over the source it is a data type member, recall that in a PDS/E you can have program object members or data members but not both in the same PDS/E.

The doc not stating what kind of member is being created can lead people in a place where if they try to write a LOADLIB or program object would yield an error.

    The data set type to be used when creating a data set. (e.g pdse)

    MEMBER expects to be used with an existing partitioned data set.

    Choices are case-insensitive.
    required: False
    type: str
    default: PDS
    choices: KSDS, ESDS, RRDS, LDS, SEQ, PDS, PDSE, LIBRARY, BASIC, LARGE, MEMBER, HFS, ZFS

Some verbiage about what type of Member is created and a reminder that the member created is a data member and not suitable for a library.

Ansible version

No response

IBM z/OS Ansible core Version

v1.4.0-beta.2

Ansible module

zos_data_set

[ddimatos]

For added clarity, i added

            If I(state=present) and I(type=MEMBER) and the member does not exist in the data set,
            create a member formatted to store data, module completes successfully with I(changed=True).
            Note, a PDSE does not allow a mixture of formats such that there is
            executables (program objects) and data. The member created is formatted to store data,
            not an executable.