Implement object semtype in runtime #7835

Job	Run time
Build Ballerina Lang	2m 55s
Build Ballerina Distribution	42m 20s
Build Stdlib Level (2)	12m 42s
Build Stdlib Level (1)	4m 56s
Build Stdlib Level (3)	5m 21s
Build Stdlib Level (4)	2m 33s
Build Stdlib Level (5)	4m 45s
Build Stdlib Level (6)	2h 0m 19s
Build Stdlib Level (7)	2m 48s
Build Stdlib Level (8)	33m 3s
Build Stdlib Level (9)	2h 0m 18s
	5h 52m 0s

Provide feedback