[BUG] `mount.fstab_present` not idempotent in test mode

Description

kvm_mount:
  mount.fstab_present:
    - name: 'example.com:/kvm'
    - fs_file: /kvm
    - fs_vfstype: nfs4
    - not_change: true
    - fs_mntops: defaults,sec=sys

If the entry in /etc/fstab already matches, Salt will always report the following in test mode in yellow:

          ID: kvm_mount
    Function: mount.fstab_present
        Name: example.com:/kvm
      Result: None
     Comment: /kvm entry is already in /etc/fstab.
     Started: 12:32:35.298712
    Duration: 2.222 ms
     Changes:

Setup
(Please provide relevant configs and/or SLS files (be sure to remove sensitive info. There is no general set-up of Salt.)

Please be as specific as possible and give set-up details.

• on-prem machine
• VM (Virtualbox, KVM, etc. please specify)
• VM running on a cloud service, please be explicit and add details
• container (Kubernetes, Docker, containerd, etc. please specify)
• or a combination, please be explicit
• jails if it is FreeBSD
• classic packaging
• onedir packaging
• used bootstrap to install

Steps to Reproduce the behavior
(Include debug logs if possible and relevant)

Expected behavior

It should report in green with no pending changes.

Screenshots
If applicable, add screenshots to help explain your problem.

Versions Report

PASTE HERE

Additional context

I will submit a patch.

Start by locating Salt's mount.fstab_present implementation and its existing tests, then reproduce the reported behavior with a matching /etc/fstab entry and test mode enabled. Done means an already-matching entry reports green with no pending changes, while changes still appear when needed.