KCI-843 make api key and secret required when creating ksql

[lct45]

Per KCI-843 make api keys and secrets mandatory when creating a new ksqlDB app through the CLI as this is the new process.

Test&Review

updated existing unit + integration testing to reflex mandatory flags

[lct45]

manual testing:

lthomas@Leah-Thomas-MBP16 confluent_cli % dist/ccloud/ccloud_$(go env GOOS)_$(go env GOARCH)/ccloud ksql app create leah_test
Error: required flag(s) "api-key", "api-secret" not set
Usage:
ccloud ksql app create [flags]

Flags:
--csu int32 Number of CSUs to use in the cluster. (default 4)
-o, --output string Specify the output format as "human", "json", or "yaml". (default "human")
--api-key string REQUIRED: Kafka API key for the ksqlDB cluster to use.
--api-secret string REQUIRED: Secret for the Kafka API key.
--environment string Environment ID.
--cluster string Kafka cluster ID.
--context string CLI context name.

Global Flags:
-h, --help Show help for this command.
-v, --verbose count Increase verbosity (-v for warn, -vv for info, -vvv for debug, -vvvv for trace).

lthomas@Leah-Thomas-MBP16 confluent_cli % dist/ccloud/ccloud_$(go env GOOS)_$(go env GOARCH)/ccloud ksql app create leah_test --api-key key --api-secret secret --cluster lkc-q0n3p
+--------------+----------------------------------------------------------+
| Id | lksqlc-v1ymyn |
| Name | leah_test |
| Topic Prefix | pksqlc-mo20q |
| Kafka | lkc-q0n3p |
| Storage | 500 |
| Endpoint | https://pksqlc-mo20q.us-west-2.aws.devel.cpdev.cloud:443 |
| Status | PROVISIONING |
+--------------+----------------------------------------------------------+

[brianstrauch]

LGTM!