fix(template-typescript-webpack): adjust ts-loader module rule syntax

[malept]

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Summarize your changes:

ts-loader was not being loaded for TypeScript files.

Also, be more strict about the exclude regex.

ISSUES CLOSED: #1378

[codecov]

Codecov Report

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@@            Coverage Diff            @@
##             master    #1388   +/-   ##
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  Coverage          ?   70.08%           
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  Files             ?       72           
  Lines             ?     2099           
  Branches          ?      389           
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  Hits              ?     1471           
  Misses            ?      454           
  Partials          ?      174

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