Empty MPD C.21.0 on surface contamination monitoring

[ftessier]

The MPD C.21.0 on surface contamination and monitoring is empty. It should be filled with relevant information or else removed.

https://github.com/ftessier/cirms/blob/779d408359038271d98cd8d3c321b004db6c91e5/needs-report/metrology-needs/safety-security/C.21.0-surface-contamination.md?plain=1#L1-L19