Update lengthen time-out time for t/re/re.t.

Update lengthen time-out time for t/re/re.t.

When we carry out this test on SH4, it becomes the time-out.
2 seconds are set in watchdog, but are too short for SH4.
This patch was changed for 10 seconds.

$ time ./perl  t/re/re.t
1..19
ok 1 - is_regexp(REGEXP ref)
ok 2 - is_regexp(REGEXP)
ok 3 - is_regexp("")
ok 4 - regexp_pattern[0] (ref)
ok 5 - regexp_pattern[1] (ref)
ok 6 - scalar regexp_pattern (ref)
ok 7 - regexp_pattern[0] (bare REGEXP)
ok 8 - regexp_pattern[1] (bare REGEXP)
ok 9 - scalar regexp_pattern (bare REGEXP)
ok 10 - !regexp_pattern("")
ok 11 - regnames
ok 12 - regnames
ok 13 - regnames in scalar context
ok 14 - regnames
ok 15
ok 16
ok 17
ok 18
ok 19 - Didn't loop

real    0m7.482s
user    0m3.848s
sys     0m0.036s