Add Dockerfile and docs for building Cloudberry Docker Images #3603

Job	Run time
check-skip	2s
prepare-test-matrix	4s
Build Apache Cloudberry RPM	12m 56s
RPM Install Test Apache Cloudberry	1m 40s
pax-ic-good-opt-off	21m 18s
pax-ic-isolation2-opt-off	23m 27s
pax-ic-good-opt-on	27m 31s
ic-singlenode	8m 9s
pax-ic-isolation2-opt-on	22m 42s
ic-expandshrink	4m 39s
ic-good-opt-on	30m 1s
ic-gpcontrib	4m 5s
ic-diskquota	10m 26s
ic-contrib	4m 31s
ic-good-opt-off	25m 35s
ic-isolation2-hot-standby	5m 2s
ic-isolation2-crash	5m 18s
ic-isolation2	36m 35s
ic-cbdb-parallel	28m 35s
ic-fixme	3m 41s
ic-parallel-retrieve-cursor	4m 25s
ic-resgroup-v2	20m 0s
Generate Apache Cloudberry Build Report	4s
	5h 0m 46s

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