### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

CopyObject API does not check precondition headers such as `x-amz-copy-source-if-modified-since`. Instead it seems to always copy the object.

### Expected Behavior

The API should return a 412 response with content similar to:

```
<Error><Code>PreconditionFailed</Code><Message>At least one of the pre-conditions you specified did not hold</Message><Condition>x-amz-copy-source-If-Modified-Since</Condition><RequestId>14HR9PXJRG5B1GR5</RequestId><HostId>HztBs2jYea1fzzPWo1JWy33NQJqo1S1IsK62rkbnVEI04PnGNCi8sPVrichGQxH3FQwLA2RIyF4=</HostId></Error>
```

### How are you starting LocalStack?

With a docker-compose file

### Steps To Reproduce

#### How are you starting localstack (e.g., `bin/localstack` command, arguments, or `docker-compose.yml`)

    docker run localstack/localstack

#### Client commands (e.g., AWS SDK code snippet, or sequence of "awslocal" commands)

```
aws s3  --profile localstack --endpoint-url http://s3.localhost.localstack.cloud:4566 \
  ls s3://net-amazon-s3-test/Makefile.am
2023-01-25 10:47:40        537 Makefile.am

aws s3api copy-object --copy-source net-amazon-s3-test/Makefile.am --key Makefile.am.2 \
  --bucket net-amazon-s3-test2 --profile localstack --endpoint-url http://s3.localhost.localstack.cloud:4566 \
  --copy-source-if-modified-since "Wed, 25 Jan 2023 16:16:27 GMT"
{
    "CopyObjectResult": {
        "ETag": "\"46ada9d1fe8f8a311ff4504c226e061c\"",
        "LastModified": "2023-01-25T16:18:43+00:00"
    }
}
```

### Environment

```markdown
- OS: penguin
- LocalStack: latest
```


### Anything else?

_No response_
if bucket.encryption:
            bucket_key_enabled = bucket_key_enabled or bucket.encryption["Rule"].get(
                "BucketKeyEnabled", False
            )
            kms_key_id = kms_key_id or bucket.encryption["Rule"][
                "ApplyServerSideEncryptionByDefault"
            ].get("KMSMasterKeyID")
            encryption = (
                encryption
                or bucket.encryption["Rule"]["ApplyServerSideEncryptionByDefault"]["SSEAlgorithm"]
            )
        if isinstance(value, bytes):
            value = BytesIO(value)
        new_key = StreamedFakeKey(
            name=key_name,
            bucket_name=bucket_name,
            value=value,
            account_id=self.account_id,
            storage=storage,
            etag=etag,
            is_versioned=bucket.is_versioned,
            
            version_id=str(random.uuid4()) if bucket.is_versioned else "null",
            multipart=multipart,
            encryption=encryption,
            kms_key_id=kms_key_id,
            bucket_key_enabled=bucket_key_enabled,
            lock_mode=lock_mode,
            lock_legal_status=lock_legal_status,