New EA Metropolis build

[Vladimir Kozlov]

The build at the Project Metropolis Early Access page [1] has been refreshed. It was updated to JDK 15.

Binaries are based on Metropolis repository [2] which was synced with jdk-15+36 (JDK 15 build 36).

Graal in Metropolis is based on GraalVM CE version of Graal [3]. It was updated up to GR-24572 commit [4] and additional 
patch was applied [5] to enable libgraal build with JDK 15.

Regards,
Vladimir Kozlov

[1] https://jdk.java.net/metropolis/
[2] https://github.com/openjdk/metropolis
[3] https://github.com/oracle/graal
[4] [GR-24572] JDK15 java.lang.invoke.MemberName is reachable.
https://github.com/oracle/graal/commit/b0735cd5fb384cfdb522488edf1d83b013507d72
[5] [GR-25120] Fixed leaked indirect java constants on jdk15.
https://github.com/oracle/graal/commit/e82d1090c23493a6d665e579cacad8241ea75318