gnu: java: Use HTTPS for osgi.org home pages.

* gnu/packages/java.scm (java-osgi-annotation, java-osgi-core)
(java-osgi-service-event, java-osgi-cmpn)
(java-osgi-service-component-annotations, java-osgi-dto, java-osgi-resource)
(java-osgi-namespace-contract, java-osgi-namespace-extender)
(java-osgi-namespace-service, java-osgi-util-function)
(java-osgi-util-promise, java-osgi-service-metatype-annotations)
(java-osgi-service-repository, java-osgi-framework, java-osgi-service-log)
(java-osgi-service-jdbc, java-osgi-service-resolver, java-osgi-util-tracker)
(java-osgi-service-cm, java-osgi-service-packageadmin)[home-page]: Use HTTPS.