Remove rule configure_opensc_nss_db from RHEL8 product.

[ggbecker]

Description:

• Remove rule configure_opensc_nss_db from RHEL8 product. This PR is part of Fix remediation for rule configure_opensc_nss_db #4776, but I decided to make the RHEL8 rule removal separated as it can be part of release 0.1.46. This rule is failing on RHEL8 PCI-DSS. See sections Smart cards in Firefox browser or Thunderbird and Register third party PKCS #11 module to p11-kit on RHEL8 article: https://access.redhat.com/articles/4253861 which confirms that OpenSC is set by default on RHEL8

Rationale:

• The rule is not applicable to RHEL8. OpenSC is set by default on RHEL8. Additionally RHEL8 does not contain pkcs11-switch tool.

[yuumasato]

LGTM, thanks.

[ggbecker]

Description:

* Remove rule configure_opensc_nss_db from RHEL8 product. This PR is part of #4776, but I decided to make the RHEL8 rule removal separated as it can be part of release 0.1.46. This rule is failing on RHEL8 PCI-DSS. See sections `Smart cards in Firefox browser or Thunderbird` and `Register third party PKCS #11 module to p11-kit` on RHEL8 article: https://access.redhat.com/articles/4253861 which confirms that OpenSC is set by default on RHEL8

I discovered a few things: OpenSC is set by default but it needs to be installed (opensc package). When you install opensc, it creates the file /usr/share/p11-kit/modules/opensc.module which contains the entry module: opensc-pkcs11.so and p11-kit knows how to load the library for the applications which will be using the library, e.g. nss (which is consumed by firefox/thunderbird)

We could change the approach of this rule to something like:

• check if the /usr/share/p11-kit/modules/opensc.module which points to correct library, and the remediation would be installing opensc package.

@yuumasato any thoughts on that?