ipatests: Suppress list trust or certificates
There are tons of useless information in test's runner log on
server uninstallation about list trust and certificates, such
as:
```
RUN ['trust', 'list']
pkcs11:id=%D2%87%B4%E3%DF%37%27%93%55%F6%56%EA%81%E5%36%CC%8C%1E%3F%BD;type=cert
type: certificate
label: ACCVRAIZ1
trust: anchor
category: authority
pkcs11:id=%F7%7D%C5%FD%C4%E8%9A%1B%77%64%A7%F5%1D%A0%CC%BF%87%60%9A%6D;type=cert
type: certificate
label: AC RAIZ FNMT-RCM
trust: anchor
category: authority
pkcs11:id=%52%D8%88%3A%C8%9F%78%66%ED%89%F3%7B%38%70%94%C9%02%02%36%D0;type=cert
type: certificate
label: Actalis Authentication Root CA
trust: anchor
category: authority
...
```
This improves the readability of test logs.
Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>