Bump handlebars from 4.7.6 to 4.7.7 in /samples/react-calendar-feed

Bumps [handlebars](https://github.com/wycats/handlebars.js) from 4.7.6 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/v4.7.6...v4.7.7)

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

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

samples/react-calendar-feed/package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "react-calendar-feed",
-  "version": "5.1.0",
+  "version": "5.2.0",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
@@ -7914,7 +7914,7 @@
       "dependencies": {
         "fast-deep-equal": {
           "version": "1.1.0",
-          "resolved": "http://registry.npmjs.org/fast-deep-equal/-/fast-deep-equal-1.1.0.tgz",
+          "resolved": "https://registry.npmjs.org/fast-deep-equal/-/fast-deep-equal-1.1.0.tgz",
           "integrity": "sha1-wFNHeBfIa1HaqFPIHgWbcz0CNhQ=",
           "dev": true
         },
@@ -13562,9 +13562,9 @@
       }
     },
     "handlebars": {
-      "version": "4.7.6",
-      "resolved": "https://registry.npmjs.org/handlebars/-/handlebars-4.7.6.tgz",
-      "integrity": "sha512-1f2BACcBfiwAfStCKZNrUCgqNZkGsAT7UM3kkYtXuLo0KnaVfjKOyf7PRzB6++aK9STyT1Pd2ZCPe3EGOXleXA==",
+      "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",