Update dependency rxjs to v7

package.json

@@ -12,7 +12,7 @@
     "next": "9.5.2",
     "react": "16.13.1",
     "react-dom": "16.13.1",
-    "rxjs": "6.6.2"
+    "rxjs": "7.5.7"
   },
   "devDependencies": {
     "@fullhuman/postcss-purgecss": "2.3.0",

yarn.lock

@@ -5701,12 +5701,12 @@ run-queue@^1.0.0, run-queue@^1.0.3:
   dependencies:
     aproba "^1.1.1"
 
-rxjs@6.6.2:
-  version "6.6.2"
-  resolved "https://registry.yarnpkg.com/rxjs/-/rxjs-6.6.2.tgz#8096a7ac03f2cc4fe5860ef6e572810d9e01c0d2"
-  integrity sha512-BHdBMVoWC2sL26w//BCu3YzKT4s2jip/WhwsGEDmeKYBhKDZeYezVUnHatYB7L85v5xs0BAQmg6BEYJEKxBabg==
+rxjs@7.5.7:
+  version "7.5.7"
+  resolved "https://registry.yarnpkg.com/rxjs/-/rxjs-7.5.7.tgz#2ec0d57fdc89ece220d2e702730ae8f1e49def39"
+  integrity sha512-z9MzKh/UcOqB3i20H6rtrlaE/CgjLOvheWK/9ILrbhROGTweAi1BaFsTT9FbwZi5Trr1qNRs+MXkhmR06awzQA==
   dependencies:
-    tslib "^1.9.0"
+    tslib "^2.1.0"
 
 safe-buffer@^5.0.1, safe-buffer@^5.1.0, safe-buffer@^5.1.1, safe-buffer@^5.1.2, safe-buffer@~5.2.0:
   version "5.2.0"
@@ -6428,6 +6428,11 @@ tslib@^1.9.0:
   resolved "https://registry.yarnpkg.com/tslib/-/tslib-1.11.1.tgz#eb15d128827fbee2841549e171f45ed338ac7e35"
   integrity sha512-aZW88SY8kQbU7gpV19lN24LtXh/yD4ZZg6qieAJDDg+YBsJcSmLGK9QpnUjAKVG/xefmvJGd1WUmfpT/g6AJGA==
 
+tslib@^2.1.0:
+  version "2.4.1"
+  resolved "https://registry.yarnpkg.com/tslib/-/tslib-2.4.1.tgz#0d0bfbaac2880b91e22df0768e55be9753a5b17e"
+  integrity sha512-tGyy4dAjRIEwI7BzsB0lynWgOpfqjUdq91XXAlIWD2OwKBH7oCl/GZG/HT4BOHrTlPMOASlMQ7veyTqpmRcrNA==
+
 [email protected]:
   version "0.0.0"
   resolved "https://registry.yarnpkg.com/tty-browserify/-/tty-browserify-0.0.0.tgz#a157ba402da24e9bf957f9aa69d524eed42901a6"