Add a test ensuring that TypeReps can be stored in compact regions
My work thus far on D4085 has involved TypeReps with cyclical structure. That bit me in break011 and break024 because :force doesn't work with cyclical structures. This would also have caused trouble for storing TypeReps in compact regions. If we eventually make :force work with cyclical structures (see #14400), then cyclical TypeReps won't break the test suite but might break user code using compact regions. So let's test for that.
Trac metadata
| Trac field | Value |
|---|---|
| Version | 8.2.1 |
| Type | Task |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Test Suite |
| Test case | |
| Differential revisions | |
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| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |