package.json: remove unnecessary nyc excludes
package.json: remove unnecessary nyc excludes

The default exclude expressions for nyc includes `test{,s}/**` which
should cover all files in the test directory.  No need to explicitly
exclude it from package.json.

Signed-off-by: Kevin Locke <ffb4761cba839470133bee36aeb139f58d7dbaa9@kevinlocke.name>

kevinoid/node-project-template,kevinoid/stream-compare,kevinoid/swagger-spec-validator,kevinoid/travis-status,kevinoid/swagger-spec-validator,kevinoid/promised-read,kevinoid/stream-compare,kevinoid/appveyor-status,kevinoid/git-branch-is,kevinoid/git-branch-is,kevinoid/node-project-template,kevinoid/appveyor-status,kevinoid/travis-status,kevinoid/swagger-spec-validator,kevinoid/travis-status,kevinoid/appveyor-status,kevinoid/node-project-template,kevinoid/stream-compare,kevinoid/git-branch-is,kevinoid/promised-read,kevinoid/promised-read