Adjust output of 'rdftests' to allow of manifests

[afs]

Make the summary consistent:

... last test T-381 ...

Time: 0.133

OK (381 tests)

Tests run: 381
Failures:  0
Manifests: 4

not

... last test T-381 ...

Time: 0.133

OK (385 tests)

Run: 385
Failures: 0

The old form counted manifests as tests.

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