Switch back to mainline ember-data-fastboot

This is still on a Git SHA, because it hasn't been published, but it is
at least on a Git SHA on an actual repo, *not* a fork.

Author: chriskrycho

package.json

@@ -64,7 +64,7 @@
     "ember-composable-helpers": "^3.1.1",
     "ember-concurrency": "^2.3.7",
     "ember-data": "~3.26.0",
-    "ember-data-fastboot": "https://codeload.github.com/gaurav0/ember-data-fastboot/tar.gz/a681c9f3d3e550cc97520abd88272691170e4094",
+    "ember-data-fastboot": "https://github.com/cardstack/ember-data-fastboot#6e6fb8bbf0b405ae174160cc1e4833c5582f68cd",
     "ember-exam": "^1.0.0",
     "ember-export-application-global": "^2.0.1",
     "ember-fetch": "^8.0.4",

yarn.lock

@@ -6789,9 +6789,9 @@ ember-concurrency-decorators@^2.0.0:
     ember-compatibility-helpers "^1.2.0"
     ember-destroyable-polyfill "^2.0.2"
 
-"ember-data-fastboot@https://codeload.github.com/gaurav0/ember-data-fastboot/tar.gz/a681c9f3d3e550cc97520abd88272691170e4094":
+"ember-data-fastboot@https://github.com/cardstack/ember-data-fastboot#6e6fb8bbf0b405ae174160cc1e4833c5582f68cd":
   version "0.1.2"
-  resolved "https://codeload.github.com/gaurav0/ember-data-fastboot/tar.gz/a681c9f3d3e550cc97520abd88272691170e4094#4f6e6ca12071ace217de17b6e57fbbedb3f2a187"
+  resolved "https://github.com/cardstack/ember-data-fastboot#6e6fb8bbf0b405ae174160cc1e4833c5582f68cd"
   dependencies:
     ember-cli-babel "^6.6.0"
     ember-cli-version-checker "^2.0.0"