multus pod is in CrashLoopBackOff state due to bad certificate

    4.14 to 4.18 even in latest release

When the latest linked certificates are updated (or “trunked”) as below and the affected pod is restarted, it always ends up in a CrashLoopBackOff state. 

1. Trunk-ed the latest link certificate using below command
sh-5.1# pwd
/etc/cni/multus/certs
lrwxrwxrwx. 1 root root   59 May  2 05:26 multus-client-current.pem -> /etc/cni/multus/certs/multus-client-2025-05-02-05-26-56.pem
-rw-------. 1 root root 1.2K May  2 05:26 multus-client-2025-05-02-05-26-56.pem
sh-5.1# > multus-client-2025-05-02-05-26-56.pem

2. Restart the respective multus pod . Below logs is visible upon describing the pod
Raw2024-03-03T12:23:36+00:00 [cnibincopy] Successfully copied files in /usr/src/multus-cni/rhel9/bin/ to /host/opt/cni/bin/upgrade_b0b45aab-8242-43ff-9315-9a3ed6ede672
2024-03-03T12:23:37+00:00 [cnibincopy] Successfully moved files in /host/opt/cni/bin/upgrade_XxXxXxX-8242-43ff-9315-9a3ed6ede672 to /host/opt/cni/bin/
2024-03-03T12:23:37Z [verbose] multus-daemon started
2024-03-03T12:23:37Z [verbose] Readiness Indicator file check
2024-03-03T12:23:37Z [verbose] Readiness Indicator file check done!
I0303 12:23:37.048136  166875 certificate_store.go:130] Loading cert/key pair from "/etc/cni/multus/certs/multus-client-current.pem".
2024-03-03T12:23:37Z [error] failed to initialize the certificate manager: could not convert data from "/etc/cni/multus/certs/multus-client-current.pem" into cert/key pair: tls: failed to find any PEM data in certificate input
2024-03-03T12:23:37Z [error] error getting perNodeClient: failed to initialize the certificate manager: could not convert data from "/etc/cni/multus/certs/multus-client-current.pem" into cert/key pair: tls: failed to find any PEM data in certificate input
2024-03-03T12:23:37Z [panic] failed start the multus thick-plugin listener: failed to create the server: error getting perNodeClient: failed to initialize the certificate manager: could not convert data from "/etc/cni/multus/certs/multus-client-current.pem" into cert/key pair: tls: failed to find any PEM data in certificate input
2024-03-03T12:23:37Z [panic] ========= Stack trace output ========
2024-03-03T12:23:37Z [panic] Multus Panic
2024-03-03T12:23:37Z [panic] ========= Stack trace output end ========

3. POD always stucks in CrashloopBackoff state
    

POD always stuck in crashloopbackoff state eventhough restarting multiple time
Refer KCS [1] for more details
[1] https://access.redhat.com/solutions/7057387    

It should remove the corrupted certificate from link and create the fresh one. So pod can be started.    

 Similar problem was there with ovnkube-node pod and it got fixed in 4.17 version refer bug [1] and respected PR [2] for your reference.
[1] https://issues.redhat.com/browse/OCPBUGS-36195
[2] https://github.com/ovn-kubernetes/ovn-kubernetes/pull/4504