fix: plugins/explore-backend/package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-WEBPACK-15235959
- https://snyk.io/vuln/SNYK-JS-WEBPACK-15235969
- https://snyk.io/vuln/SNYK-JS-QS-15268416

Author: snyk-bot

plugins/explore-backend/package.json

@@ -22,14 +22,14 @@
     "postpack": "backstage-cli package postpack"
   },
   "dependencies": {
-    "@backstage/backend-common": "workspace:^",
+    "@backstage/backend-common": "0.24.1",
     "@backstage/config": "workspace:^",
     "@backstage/plugin-explore-common": "workspace:^",
-    "@backstage/plugin-search-backend-module-explore": "workspace:^",
-    "@backstage/plugin-search-common": "workspace:^",
+    "@backstage/plugin-search-backend-module-explore": "0.3.6",
+    "@backstage/plugin-search-common": "0.3.1",
     "@backstage/types": "workspace:^",
     "@types/express": "*",
-    "express": "^4.18.1",
+    "express": "^4.22.0",
     "express-promise-router": "^4.1.0",
     "lodash": "^4.17.21",
     "node-fetch": "^2.6.7",