Switch isomorphic-unfetch to cross-fetch

`isomorphic-unfetch` causes an error in the production server bundle
because of an improper import on `node-fetch`, replacing it with
`cross-fetch` fixes it.

Ref: developit/unfetch#122

package.json

@@ -12,7 +12,7 @@
     "@slonik/migrator": "^0.1.13",
     "@types/slonik": "^19.0.0",
     "esm": "^3.2.25",
-    "isomorphic-unfetch": "^3.0.0",
+    "cross-fetch": "^3.0.4",
     "next": "latest",
     "react": "^16.10.1",
     "react-dom": "^16.10.1",

pages/initial-props.tsx

@@ -1,7 +1,7 @@
 import { NextPage } from 'next';
 import Link from 'next/link';
 import Layout from '../components/Layout';
-import fetch from 'isomorphic-unfetch';
+import fetch from 'cross-fetch';
 
 type Props = {
   data: Object;

yarn.lock

@@ -1906,6 +1906,14 @@ create-hmac@^1.1.0, create-hmac@^1.1.2, create-hmac@^1.1.4:
     safe-buffer "^5.0.1"
     sha.js "^2.4.8"
 
+cross-fetch@^3.0.4:
+  version "3.0.4"
+  resolved "https://registry.yarnpkg.com/cross-fetch/-/cross-fetch-3.0.4.tgz#7bef7020207e684a7638ef5f2f698e24d9eb283c"
+  integrity sha512-MSHgpjQqgbT/94D4CyADeNoYh52zMkCX4pcJvPP5WqPsLFMKjr2TCMg381ox5qI0ii2dPwaLx/00477knXqXVw==
+  dependencies:
+    node-fetch "2.6.0"
+    whatwg-fetch "3.0.0"
+
 crypto-browserify@^3.11.0:
   version "3.12.0"
   resolved "https://registry.yarnpkg.com/crypto-browserify/-/crypto-browserify-3.12.0.tgz#396cf9f3137f03e4b8e532c58f698254e00f80ec"
@@ -3049,14 +3057,6 @@ isobject@^3.0.0, isobject@^3.0.1:
   resolved "https://registry.yarnpkg.com/isobject/-/isobject-3.0.1.tgz#4e431e92b11a9731636aa1f9c8d1ccbcfdab78df"
   integrity sha1-TkMekrEalzFjaqH5yNHMvP2reN8=
 
-isomorphic-unfetch@^3.0.0:
-  version "3.0.0"
-  resolved "https://registry.yarnpkg.com/isomorphic-unfetch/-/isomorphic-unfetch-3.0.0.tgz#de6d80abde487b17de2c400a7ef9e5ecc2efb362"
-  integrity sha512-V0tmJSYfkKokZ5mgl0cmfQMTb7MLHsBMngTkbLY0eXvKqiVRRoZP04Ly+KhKrJfKtzC9E6Pp15Jo+bwh7Vi2XQ==
-  dependencies:
-    node-fetch "^2.2.0"
-    unfetch "^4.0.0"
-
 [email protected]:
   version "24.9.0"
   resolved "https://registry.yarnpkg.com/jest-worker/-/jest-worker-24.9.0.tgz#5dbfdb5b2d322e98567898238a9697bcce67b3e5"
@@ -3613,7 +3613,7 @@ next@latest:
     webpack-hot-middleware "2.25.0"
     webpack-sources "1.4.3"
 
-[email protected], node-fetch@^2.2.0:
+[email protected]:
   version "2.6.0"
   resolved "https://registry.yarnpkg.com/node-fetch/-/node-fetch-2.6.0.tgz#e633456386d4aa55863f676a7ab0daa8fdecb0fd"
   integrity sha512-8dG4H5ujfvFiqDmVu9fQ5bOHUC15JMjMY/Zumv26oOvvVJjM67KF8koCWIabKQ1GJIa9r2mMZscBq/TbdOcmNA==
@@ -5688,7 +5688,7 @@ umzug@^2.2.0:
     babel-runtime "^6.23.0"
     bluebird "^3.5.3"
 
-[email protected], unfetch@^4.0.0:
+[email protected]:
   version "4.1.0"
   resolved "https://registry.yarnpkg.com/unfetch/-/unfetch-4.1.0.tgz#6ec2dd0de887e58a4dee83a050ded80ffc4137db"
   integrity sha512-crP/n3eAPUJxZXM9T80/yv0YhkTEx2K1D3h7D1AJM6fzsWZrxdyRuLN0JH/dkZh1LNH8LxCnBzoPFCPbb2iGpg==
@@ -5927,6 +5927,11 @@ [email protected]:
     watchpack "^1.6.0"
     webpack-sources "^1.4.1"
 
+[email protected]:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/whatwg-fetch/-/whatwg-fetch-3.0.0.tgz#fc804e458cc460009b1a2b966bc8817d2578aefb"
+  integrity sha512-9GSJUgz1D4MfyKU7KRqwOjXCXTqWdFNvEr7eUBYchQiVc744mqK/MzXPNR2WsPkmkOa4ywfg8C2n8h+13Bey1Q==
+
 wide-align@^1.1.0:
   version "1.1.3"
   resolved "https://registry.yarnpkg.com/wide-align/-/wide-align-1.1.3.tgz#ae074e6bdc0c14a431e804e624549c633b000457"