Update README.md #8900

Job	Run time
Build Ballerina Lang	8m 11s
Build Stdlib Level (1)	3m 49s
Build Ballerina Distribution	1h 11m 57s
Build Stdlib Level (2)	4m 42s
Build Stdlib Level (3)	8m 47s
Build Stdlib Level (4)	15m 34s
Build Stdlib Level (5)	44m 12s
Build Stdlib Level (6)	25m 42s
Build Stdlib Level (7)	14m 29s
Build Stdlib Level (8)	1h 25m 18s
Build Stdlib Level (9)	4m 22s
	4h 47m 3s

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