don't copy ts files to dist/package/src

[garth]

fixes #1083

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[eromano]

I don't think is needed because src is in the npmignore

[garth]

With beta 30 installed via npm the src ts files are still there.

Also consider that when using yarn link it's not enough to .npmignore, you need a working dist folder.

[eromano]

with npm works, yes probably in link scenario nope

[eromano]

good point

[eromano]

#1113 moved here in order to let the CI run