[Security] Bump bower from 1.8.4 to 1.8.8

Bumps [bower](https://github.com/bower/bower) from 1.8.4 to 1.8.8. **This update includes security fixes.**
- [Release notes](https://github.com/bower/bower/releases)
- [Changelog](https://github.com/bower/bower/blob/master/CHANGELOG.md)
- [Commits](bower/bower@v1.8.4...v1.8.8)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot-support

package.json

@@ -20,7 +20,7 @@
   },
   "devDependencies": {
     "@ember/optional-features": "^0.7.0",
-    "bower": "^1.8.2",
+    "bower": "^1.8.8",
     "broccoli-asset-rev": "^3.0.0",
     "chai": "^4.1.2",
     "codecov": "^3.3.0",

yarn.lock

@@ -1878,10 +1878,10 @@ [email protected]:
   resolved "https://registry.yarnpkg.com/bower-endpoint-parser/-/bower-endpoint-parser-0.2.2.tgz#00b565adbfab6f2d35addde977e97962acbcb3f6"
   integrity sha1-ALVlrb+rby01rd3pd+l5Yqy8s/Y=
 
-bower@^1.8.2:
-  version "1.8.4"
-  resolved "https://registry.yarnpkg.com/bower/-/bower-1.8.4.tgz#e7876a076deb8137f7d06525dc5e8c66db82f28a"
-  integrity sha1-54dqB23rgTf30GUl3F6MZtuC8oo=
+bower@^1.8.8:
+  version "1.8.8"
+  resolved "https://registry.yarnpkg.com/bower/-/bower-1.8.8.tgz#82544be34a33aeae7efb8bdf9905247b2cffa985"
+  integrity sha512-1SrJnXnkP9soITHptSO+ahx3QKp3cVzn8poI6ujqc5SeOkg5iqM1pK9H+DSc2OQ8SnO0jC/NG4Ur/UIwy7574A==
 
 brace-expansion@^1.1.7:
   version "1.1.11"