Bump handlebars from 4.3.1 to 4.7.7 in /twistter-frontend

Bumps [handlebars](https://github.com/wycats/handlebars.js) from 4.3.1 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/v4.3.1...v4.7.7)

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

README.md

@@ -1,14 +1,2 @@
 # CS307-Team24
 CS307 Team 24 Twistter website
-
-### Images
-<p>
-  <img alt="00.png" src="./screenshots/00.png" width="1000">
-  <img alt="01.png" src="./screenshots/01.png" width="1000">
-  <img alt="02.png" src="./screenshots/02.png" width="1000">
-  <img alt="03.png" src="./screenshots/03.png" width="1000">
-  <img alt="04.png" src="./screenshots/04.png" width="1000">
-  <img alt="05.png" src="./screenshots/05.png" width="1000">
-  <img alt="06.png" src="./screenshots/06.png" width="1000">
-  <img alt="07.png" src="./screenshots/07.png" width="1000">
-</p>

functions/package-lock.json

@@ -518,23 +518,15 @@
       }
     },
     "ajv": {
-      "version": "6.12.6",
+      "version": "6.10.2",
-      "resolved": "https://registry.npmjs.org/ajv/-/ajv-6.12.6.tgz",
+      "resolved": "https://registry.npmjs.org/ajv/-/ajv-6.10.2.tgz",
-      "integrity": "sha512-j3fVLgvTo527anyYyJOGTYJbG+vnnQYvE0m5mmkc1TK+nxAppkCLMIL0aZ4dblVCNoGShhm+kzE4ZUykBoMg4g==",
+      "integrity": "sha512-TXtUUEYHuaTEbLZWIKUr5pmBuhDLy+8KYtPYdcV8qC+pOZL+NKqYwvWSRrVXHn+ZmRRAu8vJTAznH7Oag6RVRw==",
       "dev": true,
       "requires": {
-        "fast-deep-equal": "^3.1.1",
+        "fast-deep-equal": "^2.0.1",
         "fast-json-stable-stringify": "^2.0.0",
         "json-schema-traverse": "^0.4.1",
         "uri-js": "^4.2.2"
-      },
-      "dependencies": {
-        "fast-deep-equal": {
-          "version": "3.1.3",
-          "resolved": "https://registry.npmjs.org/fast-deep-equal/-/fast-deep-equal-3.1.3.tgz",
-          "integrity": "sha512-f3qQ9oQy9j2AhBe/H9VC91wLmKBCCU/gDOnKNAYG5hswO7BLKj09Hc5HYNz9cGI++xlpDCIgDaitVs03ATR84Q==",
-          "dev": true
-        }
       }
     },
     "ansi-escapes": {
@@ -681,14 +673,6 @@
         "readable-stream": "~1.0.32"
       }
     },
-    "busboy": {
-      "version": "0.3.1",
-      "resolved": "https://registry.npmjs.org/busboy/-/busboy-0.3.1.tgz",
-      "integrity": "sha512-y7tTxhGKXcyBxRKAni+awqx8uqaJKrSFSNFSeRG5CsWNdmy2BIK+6VGWEW7TZnIO/533mtMEA4rOevQV815YJw==",
-      "requires": {
-        "dicer": "0.3.0"
-      }
-    },
     "bytebuffer": {
       "version": "5.0.1",
       "resolved": "https://registry.npmjs.org/bytebuffer/-/bytebuffer-5.0.1.tgz",
@@ -1412,6 +1396,12 @@
         "tmp": "^0.0.33"
       }
     },
+    "fast-deep-equal": {
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/fast-deep-equal/-/fast-deep-equal-2.0.1.tgz",
+      "integrity": "sha1-ewUhjd+WZ79/Nwv3/bLLFf3Qqkk=",
+      "dev": true
+    },
     "fast-json-stable-stringify": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/fast-json-stable-stringify/-/fast-json-stable-stringify-2.0.0.tgz",