Remove superfluous .js extension support in nyc
diff --git a/nyc.config.js b/nyc.config.js
index 08d36cf..f1195d5 100644
--- a/nyc.config.js
+++ b/nyc.config.js
@@ -20,7 +20,7 @@
 
 module.exports = {
   all: true,
-  include: ['packages/*/src/**/*.[jt]s'],
+  include: ['packages/*/src/**/*.ts'],
   instrument: false,
   sourceMap: false,
   require: ['./babel-register.js'],