Code Analyzer throws Null Pointer Exception when run with no parameters

[rofrano]

Describe the bug

Running code analyzer with no parameters produces a java.lang.NullPointerException

To Reproduce
Steps to reproduce the behavior:

1. run: java -jar codeanalyzer-2.3.3.jar

You will see:

java.lang.RuntimeException: java.lang.NullPointerException
	at com.ibm.cldk.CodeAnalyzer.run(CodeAnalyzer.java:124)
	at picocli.CommandLine.executeUserObject(CommandLine.java:1767)
	at picocli.CommandLine.access$900(CommandLine.java:145)
	at picocli.CommandLine$RunLast.handle(CommandLine.java:2139)
	at picocli.CommandLine$RunLast.handle(CommandLine.java:2106)
	at picocli.CommandLine$AbstractParseResultHandler.execute(CommandLine.java:1973)
	at picocli.CommandLine.execute(CommandLine.java:1902)
	at com.ibm.cldk.CodeAnalyzer.main(CodeAnalyzer.java:113)
Caused by: java.lang.NullPointerException
	at java.base/java.io.File.<init>(File.java:278)
	at com.ibm.cldk.utils.BuildProject.downloadLibraryDependencies(BuildProject.java:223)
	at com.ibm.cldk.CodeAnalyzer.analyze(CodeAnalyzer.java:145)
	at com.ibm.cldk.CodeAnalyzer.run(CodeAnalyzer.java:122)
	... 7 more

Expected behavior

I expect code analyzer to print a nice welcome message with perhaps some help on how to use it. It could even return nothing. But throwing a NullPointer Exception should not be the default behavior.

Logs
If applicable, add logs to help explain your problem.

java.lang.RuntimeException: java.lang.NullPointerException
	at com.ibm.cldk.CodeAnalyzer.run(CodeAnalyzer.java:124)
	at picocli.CommandLine.executeUserObject(CommandLine.java:1767)
	at picocli.CommandLine.access$900(CommandLine.java:145)
	at picocli.CommandLine$RunLast.handle(CommandLine.java:2139)
	at picocli.CommandLine$RunLast.handle(CommandLine.java:2106)
	at picocli.CommandLine$AbstractParseResultHandler.execute(CommandLine.java:1973)
	at picocli.CommandLine.execute(CommandLine.java:1902)
	at com.ibm.cldk.CodeAnalyzer.main(CodeAnalyzer.java:113)
Caused by: java.lang.NullPointerException
	at java.base/java.io.File.<init>(File.java:278)
	at com.ibm.cldk.utils.BuildProject.downloadLibraryDependencies(BuildProject.java:223)
	at com.ibm.cldk.CodeAnalyzer.analyze(CodeAnalyzer.java:145)
	at com.ibm.cldk.CodeAnalyzer.run(CodeAnalyzer.java:122)
	... 7 more

Additional context
Add any other context about the problem here.