[7.0] Decompile step may occasionally fail with an OOM error

[Jonathing]

This is difficult to test, but the "solution" for now is to allow passing in custom heap sizes into Mavenizer. Though, I'd prefer that we limit how much of the MCP process we allow customization for. For decompile/recompile heap size, it's pretty justified.

[LexManos]

--decompile-memory was added in mavenizer 0.4.41 its up to you how to expose that to the gradle side.
the main thing is trying to figure out a way to determine the version of Mavenizer MinecraftForge/GradleUtils#28
We could just force the new arguments and hope people can see 'unknown argument' and assume to update it. If we could get the resolved version from Tool we could force a version check on our end.