Bump handlebars from 4.1.2 to 4.7.7 in /samples/js-myflows

Bumps [handlebars](https://github.com/wycats/handlebars.js) from 4.1.2 to 4.7.7.
- [Release notes](https://github.com/wycats/handlebars.js/releases)
- [Changelog](https://github.com/handlebars-lang/handlebars.js/blob/master/release-notes.md)
- [Commits](https://github.com/wycats/handlebars.js/compare/v4.1.2...v4.7.7)

---
updated-dependencies:
- dependency-name: handlebars
  dependency-type: indirect
...

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

samples/js-myflows/package-lock.json

@@ -7477,15 +7477,30 @@
       }
     },
     "handlebars": {
-      "version": "4.1.2",
-      "resolved": "https://registry.npmjs.org/handlebars/-/handlebars-4.1.2.tgz",
-      "integrity": "sha512-nvfrjqvt9xQ8Z/w0ijewdD/vvWDTOweBUm96NTr66Wfvo1mJenBLwcYmPs3TIBP5ruzYGD7Hx/DaM9RmhroGPw==",
+      "version": "4.7.7",
+      "resolved": "https://registry.npmjs.org/handlebars/-/handlebars-4.7.7.tgz",
+      "integrity": "sha512-aAcXm5OAfE/8IXkcZvCepKU3VzW1/39Fb5ZuqMtgI/hT8X2YgoMvBY5dLhq/cpOvw7Lk1nK/UF71aLG/ZnVYRA==",
       "dev": true,
       "requires": {
+        "minimist": "^1.2.5",
         "neo-async": "^2.6.0",
-        "optimist": "^0.6.1",
         "source-map": "^0.6.1",
-        "uglify-js": "^3.1.4"
+        "uglify-js": "^3.1.4",
+        "wordwrap": "^1.0.0"
+      },
+      "dependencies": {
+        "minimist": {
+          "version": "1.2.6",
+          "resolved": "https://registry.npmjs.org/minimist/-/minimist-1.2.6.tgz",
+          "integrity": "sha512-Jsjnk4bw3YJqYzbdyBiNsPWHPfO++UGG749Cxs6peCu5Xg4nrena6OVxOYxrQTqww0Jmwt+Ref8rggumkTLz9Q==",
+          "dev": true
+        },
+        "wordwrap": {
+          "version": "1.0.0",
+          "resolved": "https://registry.npmjs.org/wordwrap/-/wordwrap-1.0.0.tgz",
+          "integrity": "sha1-J1hIEIkUVqQXHI0CJkQa3pDLyus=",
+          "dev": true
+        }
       }
     },
     "har-schema": {
@@ -11580,24 +11595,6 @@
         "is-wsl": "^1.1.0"
       }
     },
-    "optimist": {
-      "version": "0.6.1",
-      "resolved": "https://registry.npmjs.org/optimist/-/optimist-0.6.1.tgz",
-      "integrity": "sha1-2j6nRob6IaGaERwybpDrFaAZZoY=",
-      "dev": true,
-      "requires": {
-        "minimist": "~0.0.1",
-        "wordwrap": "~0.0.2"
-      },
-      "dependencies": {
-        "minimist": {
-          "version": "0.0.10",
-          "resolved": "https://registry.npmjs.org/minimist/-/minimist-0.0.10.tgz",
-          "integrity": "sha1-3j+YVD2/lggr5IrRoMfNqDYwHc8=",
-          "dev": true
-        }
-      }
-    },
     "optionator": {
       "version": "0.8.2",
       "resolved": "https://registry.npmjs.org/optionator/-/optionator-0.8.2.tgz",
@@ -17178,12 +17175,6 @@
       "integrity": "sha1-tDFbtCFKPXBY6+7okuE/ok2YsHU=",
       "dev": true
     },
-    "wordwrap": {
-      "version": "0.0.3",
-      "resolved": "https://registry.npmjs.org/wordwrap/-/wordwrap-0.0.3.tgz",
-      "integrity": "sha1-o9XabNXAvAAI03I0u68b7WMFkQc=",
-      "dev": true
-    },
     "wrap-ansi": {
       "version": "2.1.0",
       "resolved": "https://registry.npmjs.org/wrap-ansi/-/wrap-ansi-2.1.0.tgz",