fix: package.json & package-lock.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-PRISMJS-1314893

package-lock.json

@@ -19,7 +19,7 @@
         "mathjax-node": "^2.1.1",
         "ncp": "^2.0.0",
         "node-prismjs": "^0.1.0",
-        "prismjs": "^1.30.0",
+        "prismjs": "^1.24.0",
         "redis": "^3.0.2",
         "rss": "^1.2.2",
         "showdown": "^1.9.1"
@@ -6694,13 +6694,9 @@
       }
     },
     "node_modules/prismjs": {
-      "version": "1.30.0",
+      "version": "1.24.0",
-      "resolved": "https://registry.npmjs.org/prismjs/-/prismjs-1.30.0.tgz",
+      "resolved": "https://registry.npmjs.org/prismjs/-/prismjs-1.24.0.tgz",
-      "integrity": "sha512-DEvV2ZF2r2/63V+tK8hQvrR2ZGn10srHbXviTlcv7Kpzw8jWiNTqbVgjO3IY8RxrrOUF8VPMQQFysYYYv0YZxw==",
+      "integrity": "sha512-SqV5GRsNqnzCL8k5dfAjCNhUrF3pR0A9lTDSCUZeh/LIshheXJEaP0hwLz2t4XHivd2J/v2HR+gRnigzeKe3cQ=="
-      "license": "MIT",
-      "engines": {
-        "node": ">=6"
-      }
     },
     "node_modules/process-nextick-args": {
       "version": "2.0.1",
@@ -14080,9 +14076,9 @@
       }
     },
     "prismjs": {
-      "version": "1.30.0",
+      "version": "1.24.0",
-      "resolved": "https://registry.npmjs.org/prismjs/-/prismjs-1.30.0.tgz",
+      "resolved": "https://registry.npmjs.org/prismjs/-/prismjs-1.24.0.tgz",
-      "integrity": "sha512-DEvV2ZF2r2/63V+tK8hQvrR2ZGn10srHbXviTlcv7Kpzw8jWiNTqbVgjO3IY8RxrrOUF8VPMQQFysYYYv0YZxw=="
+      "integrity": "sha512-SqV5GRsNqnzCL8k5dfAjCNhUrF3pR0A9lTDSCUZeh/LIshheXJEaP0hwLz2t4XHivd2J/v2HR+gRnigzeKe3cQ=="
     },
     "process-nextick-args": {
       "version": "2.0.1",

package.json

@@ -13,7 +13,7 @@
     "mathjax-node": "^2.1.1",
     "ncp": "^2.0.0",
     "node-prismjs": "^0.1.0",
-    "prismjs": "^1.30.0",
+    "prismjs": "^1.24.0",
     "redis": "^3.0.2",
     "rss": "^1.2.2",
     "showdown": "^1.9.1"