test(cardano-services): deregister stake key only for the test wallet

wallet1 stake key was deregistered when the second test started.
The second test used wallet2, so wallet1, and it's stake pool, ended up having a
deregistered stake key, which caused the fixtures to
contain a pool with a deregistered stake key, causing the unit tests to fail

packages/e2e/test/local-network/register-pool.test.ts

@@ -75,13 +75,13 @@ describe('local-network/register-pool', () => {
     wallet2.wallet.shutdown();
   });
 
-  beforeEach(() => unDelegateWallet(wallet1.wallet));
-
   test('does not meet pledge', async () => {
     const wallet = wallet1.wallet;
 
     await walletReady(wallet);
 
+    unDelegateWallet(wallet);
+
     const poolPubKey = await wallet1.bip32Account.derivePublicKey({
       index: 0,
       role: KeyRole.External
@@ -167,6 +167,7 @@ describe('local-network/register-pool', () => {
     const wallet = wallet2.wallet;
 
     await walletReady(wallet);
+    unDelegateWallet(wallet);
 
     const poolPubKey = await wallet2.bip32Account.derivePublicKey({
       index: 0,