Disable colors in CI build

plain text is easier to inspect / share

package.json

@@ -30,7 +30,7 @@
     "watch:content-scripts:ipfs-proxy:page": "watchify -p prundupify -t [ browserify-package-json --global ] add-on/src/contentScripts/ipfs-proxy/page.js -o add-on/dist/contentScripts/ipfs-proxy/page.js -v",
     "watch:content-scripts:ipfs-proxy:content": "nodemon --exec \"browserify -p prundupify -t brfs -t [ browserify-package-json --global ] -s IpfsProxyContent add-on/src/contentScripts/ipfs-proxy/content.js -o add-on/dist/contentScripts/ipfs-proxy/content.js -v\" --watch add-on/src/contentScripts/ipfs-proxy/content.js --watch add-on/dist/contentScripts/ipfs-proxy/page.js",
     "test": "run-s test:*",
-    "test:functional": " nyc --reporter=lcov --reporter=text mocha --color --timeout 15000 --require ignore-styles --reporter mocha-jenkins-reporter 'test/functional/**/*.test.js'",
+    "test:functional": " nyc --reporter=lcov --reporter=text mocha --timeout 15000 --require ignore-styles --reporter mocha-jenkins-reporter 'test/functional/**/*.test.js'",
     "lint": "run-s lint:*",
     "lint:standard": "standard --fix -v \"add-on/src/**/*.js\" \"test/**/*.js\"",
     "lint:web-ext": "web-ext lint -s add-on/",