chore: update dependency ts-morph to v6

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
ts-morph	dependencies	major	^5.0.0 -> ^6.0.2

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Release Notes

dsherret/ts-morph

v6.0.2

Compare Source

v6.0.1

Compare Source

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[bajtos]

Cross-posting from ts-morph's CHANGELOG, I am not able to asses impact of these changes on our CLI - I hope our test suite is good enough to catch any problems.

BREAKING CHANGES

• JSDoc#setComment(...) and #getComment(...) are now setDescription(...) and getDescription(). They also work according to Static file serve in loopback 4 #764.
• StructureTypeGuards is now Structure.
• PropertyDeclarationDeclaration and PropertyDeclarationStructure now can have a declare keyword (new in TS 3.7).
• JS docs will be written as a single line unless multi-line or starting with a newline. Additionally, getting a JS doc structure will have a newline at the start if the JS doc description is one line, but the JS doc is multi-line.
• ProjectOptions#useVirtualFileSystem is now useInMemoryFileSystem. This is a more accurate name.
• Creating a Project with useInMemoryFileSystem: true will now load in the lib files into the node_modules/typescript/lib folder.
• Due to the fix for Angular5 SDK #702, when using Project#addSourceFileAtPaths directories that do not have an ancestor directory with a source file included in the results will no longer be added to the project. If you want to ensure that a directory and all its subfolders are added, use Project#addDirectoryAtPath(path, { recursive: true }).
• FileSystemHost#glob is now asynchronous and #globSync was added.
• Renamed Directory/Project#addExistingSourceFile -> addSourceFileAtPath
• Renamed Directory/Project#addExistingSourceFileIfExists -> addSourceFileAtPathIfExists
• Renamed Directory/Project#addExistingSourceFiles -> addSourceFilesAtPaths
• Renamed Directory/Project#addExistingDirectory -> addDirectoryAtPath
• Renamed Directory/Project#addExistingDirectoryIfExists -> addDirectoryAtPathIfExists

[bajtos]

And here comes the first problem reported by our CI:

AssertionError: expected [Promise] to be rejected with a message matching /Target model primary key does not exist/, but got 'project.addExistingSourceFile is not a function'
  at next$onError (packages\testlab\node_modules\should\as-function.js:1799:14)
  at <anonymous>