[NEXUS-5957] Use try with resources

Signed-off-by: Alin Dreghiciu <adreghiciu@gmail.com>
[NEXUS-5957] Remove "/repodata" using repository API when only one yum member

Signed-off-by: Alin Dreghiciu <adreghiciu@gmail.com>
[NEXUS-5957] Write lock "/repodata/repomd.xml" of group while merging

Signed-off-by: Alin Dreghiciu <adreghiciu@gmail.com>
[NEXUS-5957] Install a merge request strategy on group repos that will fetch members repomd.xml when group repomd.xml is requested

Signed-off-by: Alin Dreghiciu <adreghiciu@gmail.com>
[NEXUS-5957] Disable DEBUG on capabilities as it only clutters the log

Also drop installation of capabilities plugin as plugin is already in oss bundle template

Signed-off-by: Alin Dreghiciu <adreghiciu@gmail.com>
[NEXUS-5957] Fix shouldReFetchProxyMetadata IT to not trigger merge by uploading to a hosted repo & drop duplicated tests

Signed-off-by: Alin Dreghiciu <adreghiciu@gmail.com>