tests: give more room for slowness in test-run-tests.t

The test expected any run-test.py run to end in less than 10 seconds. On slower
loaded CI machine, this gets slower than that. We give a bit more room to the
regexp.

tests/test-run-tests.t

@@ -1030,7 +1030,7 b' test for --time'
   # Ran 1 tests, 0 skipped, 0 failed.
   # Producing time report
   start   end     cuser   csys    real      Test
-  \s*[\d\.]{5}   \s*[\d\.]{5}   \s*[\d\.]{5}   \s*[\d\.]{5}   \s*[\d\.]{5}   test-success.t (re)
+  \s*[\d\.]{5,8}   \s*[\d\.]{5,8}   \s*[\d\.]{5,8}   \s*[\d\.]{5,8}   \s*[\d\.]{5,8}   test-success.t (re)
 
 test for --time with --job enabled
 ====================================
@@ -1041,7 +1041,7 b' test for --time with --job enabled'
   # Ran 1 tests, 0 skipped, 0 failed.
   # Producing time report
   start   end     cuser   csys    real      Test
-  \s*[\d\.]{5}   \s*[\d\.]{5}   \s*[\d\.]{5}   \s*[\d\.]{5}   \s*[\d\.]{5}   test-success.t (re)
+  \s*[\d\.]{5,8}   \s*[\d\.]{5,8}   \s*[\d\.]{5,8}   \s*[\d\.]{5,8}   \s*[\d\.]{5,8}   test-success.t (re)
 
 Skips
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