CLOUD-2956 Remove JDG stuff from cct_modules

[jmtd]

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https://issues.jboss.org/browse/CLOUD-2956

Note: JDG 6.* still reference cct_module master, but JDG 6 images
no longer exist in the container catalogue so presumably the
product will never be rebuilt.

[osnipso]

Since Data Grid 7.2, we are not using cct_modules anymore. The last version that did, which was 7.1, is now deprecated, so it's not supposed to be rebuilt. Looks good to me, please merge it. Thank you!