add null check for environment

[graemerocher]

Fixes:

java.lang.NullPointerException: Cannot invoke "io.micronaut.context.env.Environment.getPropertySources()" because "environment" is null
at io.micronaut.context.ConsoleBeanResolutionTracer.traceInitialConfiguration(ConsoleBeanResolutionTracer.java:58)
at io.micronaut.context.DefaultApplicationContext.lambda$configureContextInternal$1(DefaultApplicationContext.java:148)
at java.base/java.util.Optional.ifPresent(Optional.java:178)