Fix NPE ProjectExecutionManager.resolvePhase #648

Job	Run time
build	4m 58s
shellcheck	3m 22s
copyright	3m 19s
checkstyle	3m 27s
vscode-extension	4m 5s
spotbugs	5m 45s
javadoc	4m 5s
cli/linux-amd64	4m 49s
cli/windows-amd64	6m 32s
cli/darwin-amd64	6m 35s
tests/cli-linux	5m 10s
tests/cli-windows	6m 46s
tests/cli-functional-linux	6m 38s
tests/cli-functional-windows	7m 54s
tests/archetype-linux	4m 57s
tests/archetype-windows	6m 18s
tests/linker-linux	4m 43s
tests/linker-windows	5m 46s
tests/misc-linux	5m 36s
tests/misc-windows	7m 13s
cli-binaries	4s
test-results	5s
	1h 48m 7s

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