Bump bluebird from 2.9.25 to 3.7.1

Bumps [bluebird](https://github.com/petkaantonov/bluebird) from 2.9.25 to 3.7.1.
- [Release notes](https://github.com/petkaantonov/bluebird/releases)
- [Commits](petkaantonov/bluebird@v2.9.25...v3.7.1)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

package.json

@@ -25,7 +25,7 @@
   "main": "dist/index.js",
   "dependencies": {
     "babel-runtime": "7.0.0-beta.3",
-    "bluebird": "2.9.25",
+    "bluebird": "3.7.1",
     "forest-express": "5.1.1",
     "http-errors": "1.7.2",
     "lodash": "4.17.13",

yarn.lock

@@ -904,10 +904,6 @@ bitwise-xor@0.0.0:
   version "0.0.0"
   resolved "https://registry.yarnpkg.com/bitwise-xor/-/bitwise-xor-0.0.0.tgz#040a8172b5bb8cc562b0b7119f230b2a1a780e3d"
 
-bluebird@2.9.25:
-  version "2.9.25"
-  resolved "https://registry.yarnpkg.com/bluebird/-/bluebird-2.9.25.tgz#6e36bd04064d9534c07160b9f7f26c5a738fe16a"
-
 bluebird@3.3.4:
   version "3.3.4"
   resolved "https://registry.yarnpkg.com/bluebird/-/bluebird-3.3.4.tgz#f780fe43e1a7a6510f67abd7d0d79533a40ddde6"
@@ -916,6 +912,11 @@ bluebird@3.5.1:
   version "3.5.1"
   resolved "https://registry.yarnpkg.com/bluebird/-/bluebird-3.5.1.tgz#d9551f9de98f1fcda1e683d17ee91a0602ee2eb9"
 
+bluebird@3.7.1:
+  version "3.7.1"
+  resolved "https://registry.yarnpkg.com/bluebird/-/bluebird-3.7.1.tgz#df70e302b471d7473489acf26a93d63b53f874de"
+  integrity sha512-DdmyoGCleJnkbp3nkbxTLJ18rjDsE4yCggEwKNXkeV123sPNfOCYeDoeuOY+F2FrSjO1YXcTU+dsy96KMy+gcg==
+
 body-parser@1.18.2:
   version "1.18.2"
   resolved "https://registry.yarnpkg.com/body-parser/-/body-parser-1.18.2.tgz#87678a19d84b47d859b83199bd59bce222b10454"