Bump handlebars from 4.0.12 to 4.1.2 in /web/app

Bumps [handlebars](https://github.com/wycats/handlebars.js) from 4.0.12 to 4.1.2.
- [Release notes](https://github.com/wycats/handlebars.js/releases)
- [Changelog](https://github.com/wycats/handlebars.js/blob/master/release-notes.md)
- [Commits](handlebars-lang/handlebars.js@v4.0.12...v4.1.2)

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

web/app/yarn.lock

@@ -2189,6 +2189,11 @@ commander@~2.13.0:
   resolved "https://registry.yarnpkg.com/commander/-/commander-2.13.0.tgz#6964bca67685df7c1f1430c584f07d7597885b9c"
   integrity sha512-MVuS359B+YzaWqjCL/c+22gfryv+mCBPHAv3zyVI2GN8EY6IRP8VwtasXn8jyyhvvq84R4ImN1OKRtcbIasjYA==
 
+commander@~2.20.0:
+  version "2.20.0"
+  resolved "https://registry.yarnpkg.com/commander/-/commander-2.20.0.tgz#d58bb2b5c1ee8f87b0d340027e9e94e222c5a422"
+  integrity sha512-7j2y+40w61zy6YC2iRNpUe/NwhNyoXrYpHMrSunaMG64nRnaf96zO/KMQR4OyN/UnE5KLyEBnKHd4aG3rskjpQ==
+
 common-tags@1.8.0:
   version "1.8.0"
   resolved "https://registry.yarnpkg.com/common-tags/-/common-tags-1.8.0.tgz#8e3153e542d4a39e9b10554434afaaf98956a937"
@@ -4186,11 +4191,11 @@ handle-thing@^1.2.5:
   integrity sha1-/Xqtcmvxpf0W38KbL3pmAdJxOcQ=
 
 handlebars@^4.0.3:
-  version "4.0.12"
-  resolved "https://registry.yarnpkg.com/handlebars/-/handlebars-4.0.12.tgz#2c15c8a96d46da5e266700518ba8cb8d919d5bc5"
-  integrity sha512-RhmTekP+FZL+XNhwS1Wf+bTTZpdLougwt5pcgA1tuz6Jcx0fpH/7z0qd71RKnZHBCxIRBHfBOnio4gViPemNzA==
+  version "4.1.2"
+  resolved "https://registry.yarnpkg.com/handlebars/-/handlebars-4.1.2.tgz#b6b37c1ced0306b221e094fc7aca3ec23b131b67"
+  integrity sha512-nvfrjqvt9xQ8Z/w0ijewdD/vvWDTOweBUm96NTr66Wfvo1mJenBLwcYmPs3TIBP5ruzYGD7Hx/DaM9RmhroGPw==
   dependencies:
-    async "^2.5.0"
+    neo-async "^2.6.0"
     optimist "^0.6.1"
     source-map "^0.6.1"
   optionalDependencies:
@@ -6346,7 +6351,7 @@ minimist@1.2.0, minimist@^1.1.0, minimist@^1.1.1, minimist@^1.1.3, minimist@^1.2
 
 minimist@~0.0.1:
   version "0.0.10"
-  resolved "http://registry.npmjs.org/minimist/-/minimist-0.0.10.tgz#de3f98543dbf96082be48ad1a0c7cda836301dcf"
+  resolved "https://registry.yarnpkg.com/minimist/-/minimist-0.0.10.tgz#de3f98543dbf96082be48ad1a0c7cda836301dcf"
   integrity sha1-3j+YVD2/lggr5IrRoMfNqDYwHc8=
 
 minipass@^2.2.1, minipass@^2.3.3:
@@ -6518,10 +6523,10 @@ negotiator@0.6.1:
   resolved "https://registry.yarnpkg.com/negotiator/-/negotiator-0.6.1.tgz#2b327184e8992101177b28563fb5e7102acd0ca9"
   integrity sha1-KzJxhOiZIQEXeyhWP7XnECrNDKk=
 
-neo-async@^2.5.0:
-  version "2.5.2"
-  resolved "https://registry.yarnpkg.com/neo-async/-/neo-async-2.5.2.tgz#489105ce7bc54e709d736b195f82135048c50fcc"
-  integrity sha512-vdqTKI9GBIYcAEbFAcpKPErKINfPF5zIuz3/niBfq8WUZjpT2tytLlFVrBgWdOtqI4uaA/Rb6No0hux39XXDuw==
+neo-async@^2.5.0, neo-async@^2.6.0:
+  version "2.6.1"
+  resolved "https://registry.yarnpkg.com/neo-async/-/neo-async-2.6.1.tgz#ac27ada66167fa8849a6addd837f6b189ad2081c"
+  integrity sha512-iyam8fBuCUpWeKPGpaNMetEocMt364qkCsfL9JuhjXX6dRnguRVOfk2GZaDpPjcOKiiXCPINZC1GczQ7iTq3Zw==
 
 netmask@^1.0.6:
   version "1.0.6"
@@ -10022,7 +10027,7 @@ uglify-es@^3.3.4:
     commander "~2.13.0"
     source-map "~0.6.1"
 
-uglify-js@3.4.x, uglify-js@^3.0.13, uglify-js@^3.1.4:
+uglify-js@3.4.x, uglify-js@^3.0.13:
   version "3.4.9"
   resolved "https://registry.yarnpkg.com/uglify-js/-/uglify-js-3.4.9.tgz#af02f180c1207d76432e473ed24a28f4a782bae3"
   integrity sha512-8CJsbKOtEbnJsTyv6LE6m6ZKniqMiFWmm9sRbopbkGs3gMPPfd3Fh8iIA4Ykv5MgaTbqHr4BaoGLJLZNhsrW1Q==
@@ -10040,6 +10045,14 @@ uglify-js@^2.8.29:
   optionalDependencies:
     uglify-to-browserify "~1.0.0"
 
+uglify-js@^3.1.4:
+  version "3.6.0"
+  resolved "https://registry.yarnpkg.com/uglify-js/-/uglify-js-3.6.0.tgz#704681345c53a8b2079fb6cec294b05ead242ff5"
+  integrity sha512-W+jrUHJr3DXKhrsS7NUVxn3zqMOFn0hL/Ei6v0anCIMoKC93TjcflTagwIHLW7SfMFfiQuktQyFVCFHGUE0+yg==
+  dependencies:
+    commander "~2.20.0"
+    source-map "~0.6.1"
+
 uglify-to-browserify@~1.0.0:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/uglify-to-browserify/-/uglify-to-browserify-1.0.2.tgz#6e0924d6bda6b5afe349e39a6d632850a0f882b7"