`prif_ucobound` and `prif_coshape` report/use non-conforming trailing ucobound

[bonachea]

The F23 standard for UCOBOUND states:

The final upper cobound is the final cosubscript in the cosubscript list for the coarray that selects the image whose index is equal to the number of images in the current team.

This means the trailing ucobound reported by UCOBOUND changes based on the current team size.

The result value of COSHAPE is specified in terms of UCOBOUND, and thus the trailing value in the result also depends on the current team size.

Caffeine does not yet implement these team-sensitive semantics, instead always returning/using the trailing ucobound value supplied by the caller when the coarray descriptor was constructed.