Poorna b4f6901903
resync: Avoid concurrent access/write on map (#15286)
fixes a crash

```
fatal error: concurrent map iteration and map write
minio[19309]: goroutine 18640 [running]:
minio[19309]: runtime.throw({0x27a3399?, 0x1785?})
minio[19309]: runtime/panic.go:992 +0x71 fp=0xc0062f1c80 sp=0xc0062f1c50 pc=0x438671
minio[19309]: runtime.mapiternext(0xc0062f1e90?)
minio[19309]: runtime/map.go:871 +0x4eb fp=0xc0062f1cf0 sp=0xc0062f1c80 pc=0x41002b
minio[19309]: github.com/minio/minio/cmd.(*ReplicationPool).periodicResyncMetaSave(0xc0056c00c0, {0x4d06a48, 0xc0005b2480}, {0x4d22fc0, 0xc0015ea0
```
2022-07-13 16:29:10 -07:00
..
2021-04-23 11:58:53 -07:00
2021-04-23 11:58:53 -07:00
2021-04-23 11:58:53 -07:00
2022-06-23 23:19:24 -07:00
2021-04-23 11:58:53 -07:00