fix example env

Author: Yash094

.env.example

@@ -0,0 +1,7 @@
+# rename this file to .env and fill in the values
+# this is not required to build the packages but will significantly increase test performance
+
+# used for unit tests that hit real IPFS gateway
+# get a secret key from https://thirdweb.com/create-api-key
+# Learn more about API keys. https://portal.thirdweb.com/account/api-keys
+TW_SECRET_KEY=""