APF-2100: Schema URL fix for Card object type schema doc href

[davidpshaw]

The schema URL for the Card Responses object has moved from:

https://github.com/vmwaresamples/card-connectors-guide/wiki/Card-Responses

to:

https://github.com/vmware-samples/card-connectors-guide/wiki/Card-Responses

This PR changes the discovery to reflect this new URL.

[vmwclabot]

@davidpshaw, you must sign every commit in this pull request acknowledging our Developer Certificate of Origin before your changes are merged. This can be done by adding Signed-off-by: John Doe <john.doe@email.org> to the last line of each Git commit message. The e-mail address used to sign must match the e-mail address of the Git author. Click here to view the Developer Certificate of Origin agreement.

• Commit bdc9e3f must be signed by shawd@vmware.com

[vmwclabot]

@davidpshaw, you must sign every commit in this pull request acknowledging our Developer Certificate of Origin before your changes are merged. This can be done by adding Signed-off-by: John Doe <john.doe@email.org> to the last line of each Git commit message. The e-mail address used to sign must match the e-mail address of the Git author. Click here to view the Developer Certificate of Origin agreement.

• Commit bdc9e3f must be signed by shawd@vmware.com