chore: update CODEOWNERS with core-platform (#311)

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Updating CODEOWNERS file to swap `@MetaMask/wallet-framework-engineers`
with `@MetaMask/core-platform`.

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Author: mikesposito

.github/CODEOWNERS

@@ -4,12 +4,12 @@
 *                                       @MetaMask/accounts-engineers
 
 # Included for release purposes
-/package.json                           @MetaMask/accounts-engineers @MetaMask/wallet-framework-engineers
-/yarn.lock                              @MetaMask/accounts-engineers @MetaMask/wallet-framework-engineers
-/README.md                              @MetaMask/accounts-engineers @MetaMask/wallet-framework-engineers
+/package.json                           @MetaMask/accounts-engineers @MetaMask/core-platform
+/yarn.lock                              @MetaMask/accounts-engineers @MetaMask/core-platform
+/README.md                              @MetaMask/accounts-engineers @MetaMask/core-platform
 
-/packages/keyring-eth-hd                @MetaMask/accounts-engineers @MetaMask/wallet-framework-engineers
-/packages/keyring-eth-ledger-bridge     @MetaMask/accounts-engineers @MetaMask/wallet-framework-engineers
-/packages/keyring-eth-simple            @MetaMask/accounts-engineers @MetaMask/wallet-framework-engineers
-/packages/keyring-eth-trezor            @MetaMask/accounts-engineers @MetaMask/wallet-framework-engineers
-/packages/keyring-utils                 @MetaMask/accounts-engineers @MetaMask/wallet-framework-engineers
+/packages/keyring-eth-hd                @MetaMask/accounts-engineers @MetaMask/core-platform
+/packages/keyring-eth-ledger-bridge     @MetaMask/accounts-engineers @MetaMask/core-platform
+/packages/keyring-eth-simple            @MetaMask/accounts-engineers @MetaMask/core-platform
+/packages/keyring-eth-trezor            @MetaMask/accounts-engineers @MetaMask/core-platform
+/packages/keyring-utils                 @MetaMask/accounts-engineers @MetaMask/core-platform