Only java 11

[farodin91]

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[li-boxuan]

@farodin91 Do you think we can do this in the next major release, e.g. 2.0.0? We could send an announcement (that java 8 will no longer be supported) once 1.0.0 is released.

[farodin91]

@li-boxuan We can move this to 2.0.
We have to change the upcoming latest version in the build pipeline.

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