Removes the sh:maxCount from the observable:IMEI property of the observable:MobileDeviceFacet.

This Pull Request resolves all requirements of #521 .

Coordination

[x] Pull Request is against correct branch
[x] Pull Request is in, or reverted to, Draft status before Solutions Approval vote has passed
[x] CI passes in UCO feature branch against develop
[x] CI passes in UCO current unstable branch (2045b93)
[x] CI passes in CASE current unstable branch tracking UCO's unstable as submodule (235246a)
[x] Impact on SHACL validation reviewed for CASE-Examples
[x] Impact on SHACL validation remediated for CASE-Examples (N/A)
[x] Impact on SHACL validation reviewed for casework.github.io
[x] Impact on SHACL validation remediated for casework.github.io (N/A)
[x] Milestone linked
[x] Solutions Approval vote logged on corresponding Issue (once logged, can be taken out of Draft PR status)

ucoProject / UCO