Remove ember-promise-helpers

package.json

@@ -197,7 +197,6 @@
     "ember-parachute": "^1.0.2",
     "ember-percy": "^1.5.0",
     "ember-power-select": "^4.1.7",
-    "ember-promise-helpers": "^1.0.4",
     "ember-qrcode-shim": "^0.4.0",
     "ember-qunit": "^5.1.5",
     "ember-radio-button": "^2.0.0",

yarn.lock

@@ -10424,7 +10424,7 @@ [email protected]:
     ensure-posix-path "^1.0.2"
     semver "^5.5.0"
 
-ember-cli-babel@^6.0.0-beta.4, ember-cli-babel@^6.12.0, ember-cli-babel@^6.16.0, ember-cli-babel@^6.17.0, ember-cli-babel@^6.3.0, ember-cli-babel@^6.6.0, ember-cli-babel@^6.7.0, ember-cli-babel@^6.7.1, ember-cli-babel@^6.8.0, ember-cli-babel@^6.8.1, ember-cli-babel@^6.8.2, ember-cli-babel@^6.9.2:
+ember-cli-babel@^6.0.0-beta.4, ember-cli-babel@^6.12.0, ember-cli-babel@^6.17.0, ember-cli-babel@^6.3.0, ember-cli-babel@^6.6.0, ember-cli-babel@^6.7.0, ember-cli-babel@^6.7.1, ember-cli-babel@^6.8.0, ember-cli-babel@^6.8.1, ember-cli-babel@^6.8.2, ember-cli-babel@^6.9.2:
   version "6.18.0"
   resolved "https://registry.yarnpkg.com/ember-cli-babel/-/ember-cli-babel-6.18.0.tgz#3f6435fd275172edeff2b634ee7b29ce74318957"
   integrity sha512-7ceC8joNYxY2wES16iIBlbPSxwKDBhYwC8drU3ZEvuPDMwVv1KzxCNu1fvxyFEBWhwaRNTUxSCsEVoTd9nosGA==
@@ -11861,13 +11861,6 @@ ember-power-select@^4.1.7:
     ember-text-measurer "^0.6.0"
     ember-truth-helpers "^2.1.0 || ^3.0.0"
 
-ember-promise-helpers@^1.0.4:
-  version "1.0.9"
-  resolved "https://registry.yarnpkg.com/ember-promise-helpers/-/ember-promise-helpers-1.0.9.tgz#4559dd4a09be1a2725eddd7146169d2d53a92e7a"
-  integrity sha512-BDcx2X28baEL0YMKSmDGQzvdyfiFSlx4Byf34hVrAw6W7VO17YYLjeXPebVBOXLA1BMWmUo0Bb2pZRZ09MQYYA==
-  dependencies:
-    ember-cli-babel "^6.16.0"
-
 ember-qrcode-shim@^0.4.0:
   version "0.4.0"
   resolved "https://registry.yarnpkg.com/ember-qrcode-shim/-/ember-qrcode-shim-0.4.0.tgz#bc4c61e8c33c7e731e98d68780a772d59eec4fc6"