Here we are seeing incoming Oversized frames on this interface xe-0/0/13:2 which is connected to Google GCP

GCP offers 1500 B MTU (at most). 

Please note GCP offers 1500 B MTU << that's without macsec. 

From RSI, we can see; 

Physical interface: xe-0/0/13:2, Enabled, Physical link is Up

 Interface index: 264, SNMP ifIndex: 713, Generation: 283

 Description: "Customer description"

 Link-level type: Ethernet, MTU: 1518, MRU: 1526, LAN-PHY mode, Speed: 10Gbps, BPDU Error: None, Loop Detect PDU Error: None, MAC-REWRITE Error: None,

 MAC statistics:           Receive     Transmit

  MAC pause frames             0        0

  Oversized frames            973

We can check that Oversized frames on this interface are connected to Google GCP, which means google is sending packets higher than its MRU 1526. Based on Juniper documentation, we won't be sending any ICMP packet.

BEST PRACTICE: When enabling MACsec, we recommend that you examine your interface MTU, adjusting it for MACsec overhead, which is 32 bytes.

'set interfaces ae0.1100 family inet mtu 1476 '
 'set interfaces ae0.1100 family inet mtu 1474 '

As mentioned earlier, with MACSEC enabled, we need to adjust MTU accordingly by increasing 24-32B, or you can check with the other vendor if there are any MTU best practices to follow.

This is the recommendation from Juniper: https://www.juniper.net/documentation/us/en/software/junos/security-services/topics/task/macsec.html