build: bump aetna from 1.0.0-alpha.14 to 1.0.0-alpha.15 (#96 An error occurred )

Bumps [aetna](https://github.com/pressbooks/aetna) from 1.0.0-alpha.14 to 1.0.0-alpha.15.
- [Release notes](https://github.com/pressbooks/aetna/releases/tag/untagged-30dae06d864127306cdf)
- [Commits](https://github.com/pressbooks/aetna/compare/1.0.0-alpha.14...1.0.0-alpha.15)

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "@pressbooks/pressbooks-aldine",
-  "version": "1.0.0-rc.1",
+  "version": "1.0.0-rc.2",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
@@ -284,9 +284,9 @@
       }
     },
     "aetna": {
-      "version": "1.0.0-alpha.14",
-      "resolved": "https://registry.npmjs.org/aetna/-/aetna-1.0.0-alpha.14.tgz",
-      "integrity": "sha512-ULfjypnNmd5BlPm1PBp8Ga0k8t+GlkHfi5VDaAeH4qEJYgMA5AdsxoMQbR/KTITIa/aP9tVVzzhLH5Xgw5h1Ew==",
+      "version": "1.0.0-alpha.15",
+      "resolved": "https://registry.npmjs.org/aetna/-/aetna-1.0.0-alpha.15.tgz",
+      "integrity": "sha512-GeNRopb4RXL+PPt5HbPyWfwH0bMAEkDYc5YHae0g8J0sQdPmdZG2Lq9gZpW47dJ7h8rFig57Un11S0f3qWqJcg==",
       "requires": {
         "@frctl/fractal": "1.1.7"
       }

package.json

@@ -57,7 +57,7 @@
     "pressbooks-build-tools": "^0.10.0"
   },
   "dependencies": {
-    "aetna": "^1.0.0-alpha.14",
+    "aetna": "^1.0.0-alpha.15",
     "isotope-layout": "^3.0.5",
     "jquery-bridget": "^2.0.1",
     "js-cookie": "^2.2.0",

yarn.lock

@@ -178,9 +178,9 @@ adjust-sourcemap-loader@^1.1.0:
     object-path "^0.9.2"
     regex-parser "^2.2.1"
 
-aetna@^1.0.0-alpha.14:
-  version "1.0.0-alpha.14"
-  resolved "https://registry.yarnpkg.com/aetna/-/aetna-1.0.0-alpha.14.tgz#676bf8d23d85d36c0e10c0e1ecc576397283b3cc"
+aetna@^1.0.0-alpha.15:
+  version "1.0.0-alpha.15"
+  resolved "https://registry.yarnpkg.com/aetna/-/aetna-1.0.0-alpha.15.tgz#bfa8a6965042ad33d9878196b3b28af34263cdc8"
   dependencies:
     "@frctl/fractal" "^1.1.7"