SELinux is preventing /usr/sbin/NetworkManager from unlink access on the file resolv.conf.

*****  Plugin restorecon (94.8 confidence) suggests   ************************

If you want to fix the label. 
resolv.conf default label should be net_conf_t.
Then you can run restorecon. The access attempt may have been stopped due to insufficient permissions to access a parent directory in which case try to change the following command accordingly.
Do
# /sbin/restorecon -v resolv.conf

*****  Plugin catchall_labels (5.21 confidence) suggests   *******************

If you want to allow NetworkManager to have unlink access on the resolv.conf file
Then you need to change the label on resolv.conf
Do
# semanage fcontext -a -t FILE_TYPE 'resolv.conf'
where FILE_TYPE is one of the following: NetworkManager_etc_rw_t, NetworkManager_tmp_t, NetworkManager_var_lib_t, NetworkManager_var_run_t, dhcpc_state_t, dhcpc_var_run_t, dnsmasq_var_run_t, hostname_etc_t, krb5_host_rcache_t, named_cache_t, net_conf_t, pppd_var_run_t, ssh_home_t, systemd_passwd_var_run_t.
Then execute:
restorecon -v 'resolv.conf'


*****  Plugin catchall (1.44 confidence) suggests   **************************

If you believe that NetworkManager should be allowed unlink access on the resolv.conf file by default.
Then you should report this as a bug.
You can generate a local policy module to allow this access.
Do
allow this access for now by executing:
# ausearch -c 'NetworkManager' --raw | audit2allow -M my-NetworkManager
# semodule -X 300 -i my-NetworkManager.pp

Additional Information:
Source Context                system_u:system_r:NetworkManager_t:s0
Target Context                system_u:object_r:etc_t:s0
Target Objects                resolv.conf [ file ]
Source                        NetworkManager
Source Path                   /usr/sbin/NetworkManager
Port                          <Unknown>
Host                          oldmachine
Source RPM Packages           NetworkManager-1.46.0-13.el9_4.x86_64
Target RPM Packages           
SELinux Policy RPM            selinux-policy-targeted-38.1.35-2.el9_4.2.noarch
Local Policy RPM              selinux-policy-targeted-38.1.35-2.el9_4.2.noarch
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Host Name                     oldmachine
Platform                      Linux oldmachine
                              5.14.0-427.16.1.el9_4.x86_64 #1 SMP
                              PREEMPT_DYNAMIC Thu May 9 18:15:59 EDT 2024 x86_64
                              x86_64
Alert Count                   14
First Seen                    2024-09-02 07:33:51 BST
Last Seen                     2024-09-03 19:58:39 BST
Local ID                      5f646ea4-8e76-41fb-b0f7-7cab4e2d9c01

Raw Audit Messages
type=AVC msg=audit(1725389919.934:1114): avc:  denied  { unlink } for  pid=1337 comm="NetworkManager" name="resolv.conf" dev="dm-1" ino=527389 scontext=system_u:system_r:NetworkManager_t:s0 tcontext=system_u:object_r:etc_t:s0 tclass=file permissive=0


type=SYSCALL msg=audit(1725389919.934:1114): arch=x86_64 syscall=rename success=no exit=EACCES a0=563de8727120 a1=563de698ffe8 a2=0 a3=31 items=0 ppid=1 pid=1337 auid=4294967295 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=(none) ses=4294967295 comm=NetworkManager exe=/usr/sbin/NetworkManager subj=system_u:system_r:NetworkManager_t:s0 key=(null)

Hash: NetworkManager,NetworkManager_t,etc_t,file,unlink