Update KMS method signatures to standardize on KeyringException

It came up during the review of [] that it doesn't make a lot of sense
for encrypt() and decrypt() to not throw the same kinds of Exceptions,
especially not for the same kind of problem, just because one happens to use a
Retrier in its internal implementation and the other doesn't.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=201054057

java/google/registry/keyring/kms/KmsKeyring.java

@@ -192,7 +192,7 @@ public class KmsKeyring implements Keyring {
 
     try {
       return kmsConnection.decrypt(secret.getName(), encryptedData);
-    } catch (IOException e) {
+    } catch (Exception e) {
       throw new KeyringException(
           String.format("CloudKMS decrypt operation failed for secret %s", keyName), e);
     }