fix: downgrade isomorphic-unfetch to 4.0.0

Without this patch people were experiencing problems when bundling the
SDK. See issue ToucanProtocol#95 ToucanProtocol#95

The problem is that `isomorphic-unfetch` 4.0.2 upgraded to `unfetch`
5.0.0 which currently has an issue with their module exports leading to
an error when bundling the lib itself or any other lib that depends on
`unfetch`.

See this PR for more information: developit/unfetch#164

Once the PR above is merged we can go back to the latest `isomorphic-unfetch`
version.

Author: pheuberger

package.json

@@ -28,7 +28,7 @@
     "@urql/core": "^2.5.0",
     "ethers": "^5.6.4",
     "graphql": "^16.5.0",
-    "isomorphic-unfetch": "^4.0.2",
+    "isomorphic-unfetch": "4.0.0",
     "typedoc": "^0.25.1",
     "typedoc-plugin-markdown": "^3.16.0"
   },

yarn.lock

@@ -5975,13 +5975,13 @@ 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@^4.0.2:
-  version "4.0.2"
-  resolved "https://registry.yarnpkg.com/isomorphic-unfetch/-/isomorphic-unfetch-4.0.2.tgz#5fc04eeb1053b7b702278e2cf7a3f246cb3a9214"
-  integrity sha512-1Yd+CF/7al18/N2BDbsLBcp6RO3tucSW+jcLq24dqdX5MNbCNTw1z4BsGsp4zNmjr/Izm2cs/cEqZPp4kvWSCA==
+isomorphic-unfetch@4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/isomorphic-unfetch/-/isomorphic-unfetch-4.0.0.tgz#439422d68014e9355680e011ec05878c3a65672d"
+  integrity sha512-faQdcv4iQsZXTQIRWVVjfibY7CRxLBpvafqrc5ZgEPUXkDDiQu4nqXRtG5SuJUurW2XHM9uwPuna2r4Px2iNKA==
   dependencies:
     node-fetch "^3.2.0"
-    unfetch "^5.0.0"
+    unfetch "^4.2.0"
 
 isstream@~0.1.2:
   version "0.1.2"
@@ -9660,10 +9660,10 @@ undici@^5.4.0:
   resolved "https://registry.yarnpkg.com/undici/-/undici-5.5.1.tgz#baaf25844a99eaa0b22e1ef8d205bffe587c8f43"
   integrity sha512-MEvryPLf18HvlCbLSzCW0U00IMftKGI5udnjrQbC5D4P0Hodwffhv+iGfWuJwg16Y/TK11ZFK8i+BPVW2z/eAw==
 
-unfetch@^5.0.0:
-  version "5.0.0"
-  resolved "https://registry.yarnpkg.com/unfetch/-/unfetch-5.0.0.tgz#8a5b6e5779ebe4dde0049f7d7a81d4a1af99d142"
-  integrity sha512-3xM2c89siXg0nHvlmYsQ2zkLASvVMBisZm5lF3gFDqfF2xonNStDJyMpvaOBe0a1Edxmqrf2E0HBdmy9QyZaeg==
+unfetch@^4.2.0:
+  version "4.2.0"
+  resolved "https://registry.yarnpkg.com/unfetch/-/unfetch-4.2.0.tgz#7e21b0ef7d363d8d9af0fb929a5555f6ef97a3be"
+  integrity sha512-F9p7yYCn6cIW9El1zi0HI6vqpeIvBsr3dSuRO6Xuppb1u5rXpCPmMvLSyECLhybr9isec8Ohl0hPekMVrEinDA==
 
 union-value@^1.0.0:
   version "1.0.1"