chore: update all dependencies for multi test app

tests/apps/multi/Gemfile

@@ -1,6 +1,6 @@
 source "https://rubygems.org"
 
-ruby '2.6.8'
+ruby '2.7.5'
 
 gem 'compass', ">= 1.0.1"
 gem 'sass-globbing'

tests/apps/multi/Gemfile.lock

@@ -1,7 +1,7 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    chunky_png (1.3.11)
+    chunky_png (1.4.0)
     compass (1.0.3)
       chunky_png (~> 1.2)
       compass-core (~> 1.0.2)
@@ -14,10 +14,10 @@ GEM
       sass (>= 3.3.0, < 3.5)
     compass-import-once (1.0.5)
       sass (>= 3.2, < 3.5)
-    ffi (1.11.1)
+    ffi (1.15.5)
-    multi_json (1.14.1)
+    multi_json (1.15.0)
-    rb-fsevent (0.10.3)
+    rb-fsevent (0.11.1)
-    rb-inotify (0.10.0)
+    rb-inotify (0.10.1)
       ffi (~> 1.0)
     sass (3.4.25)
     sass-globbing (1.1.5)
@@ -29,3 +29,9 @@ PLATFORMS
 DEPENDENCIES
   compass (>= 1.0.1)
   sass-globbing
+
+RUBY VERSION
+   ruby 2.7.5p203
+
+BUNDLED WITH
+   2.1.4

tests/apps/multi/bower.json

@@ -16,5 +16,6 @@
   ],
   "dependencies": {
     "bootstrap-sass": "twbs/bootstrap-sass#~3.1.1"
-  }
+  },
+  "registry": "https://registry.bower.io"
 }

tests/apps/multi/package.json

@@ -1,16 +1,16 @@
 {
   "author": "Al Johri",
   "dependencies": {
-    "bower": "^1.3.1",
+    "bower": "^1.8.0",
-    "grunt": "~0.4.5",
+    "grunt": "~1.4.1",
-    "grunt-cli": "~0.1.13",
+    "grunt-cli": "~1.4.3",
-    "grunt-contrib-compass": "~1.0.1",
+    "grunt-contrib-compass": "~1.1.1",
-    "load-grunt-tasks": "~1.0.0",
+    "load-grunt-tasks": "~5.1.0",
-    "tmp": "0.0.23"
+    "tmp": "0.2.1"
   },
   "description": "Test application for heroku multi buildpack.",
   "engines": {
-    "node": "6.x.x",
+    "node": "12.x.x",
     "npm": "6.x.x"
   },
   "license": "ISC",