Added Micronaut SnapStart version (#12)

[dmahapatro]

Issue #, if available:

12

Description of changes: Added SnapStart sample for Micronaut

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[yawkat]

our benchmarks test somewhat differently ofc but relative to the other frameworks it seems about right (slightly ahead of spring boot, behind quarkus)

[dmahapatro]

Thanks @yawkat and @alvarosanchez. Looking at the PR do you see any other areas of improvement other than Eager Initialization of Singletons and SnapStart in general.

[ravsrin]

Looks good. Nice job!