[collector] useGOMEMLIMIT: true makes otel col startup faild

[JaredTan95]

I tested with useGOMEMLIMIT: true after #900 merged But I got the following errors and otel col could not startup:

GOMEMLIMIT=1024Mi
fatal error: malformed GOMEMLIMIT; see `go doc runtime/debug.SetMemoryLimit`

runtime stack:
runtime.throw({0x7ca4cb5?, 0xa?})
	runtime/panic.go:1077 +0x5c fp=0x7ffc561f55c8 sp=0x7ffc561f5598 pc=0x43ba5c

so, I change GOMEMLIMIT=1024Mi into GOMEMLIMIT=1024MiB according go runtime docs and otel-col startup success.

[TylerHelmuth]

This was called out here, and I thought I included that suggestion in the suggestion batch, but it looks like I missed it: #900 (comment). Are you able to submit a PR to fix this?