npm package cleanup

[jessehouwing]

The final 0.22.2 npm package contains a few things that cause a few issues.

Things I think should be stripped from the published package:

test-results.xml
tfx-cli-0.22.2.tgz
typings\
.devcontainer\
_tests\
gulp.cmd
.editorconfig
.gitattributes
.mocharc.json
tsconfig.tests.json
tsd.json

This adds a good useless 400Kb to the package size and also caused the azure-devops-extension-tasks to fail installation on Azure Devops, cause all the task.json files in the _tests folder are somehow parsed during extension & task installation from the marketplace when tfx-cli is embedded in a build task extension.

The npm published package can probably do without these file.

Related: microsoft/vsmarketplace#1483