tests: increase timeout for slow test
Test case `test-sparse-revlog.t` need some artifact (a bundle) build before it
can run. The artifact is expensive to build, but can be reused from one run to
the other. We are about to update that test to make the artifact building
automatic if `--allow-slow-tests` is passed. However, we need a bump the
timeout a bit to make sure the artifact building as time to finish.
We could maybe teach run-tests.py how to directly handle such artifacts.
However since there is only one of them for now, this seems premature.
There are also some room to speed up the bundle creation for
test-sparse-revlog.t
$ hg init repo
$ cd repo
$ touch foo
$ hg ci -Am 'add foo'
adding foo
$ hg up -C null
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
this should be stored as a delta against rev 0
$ echo foo bar baz > foo
$ hg ci -Am 'add foo again'
adding foo
created new head
$ hg debugindex foo
rev linkrev nodeid p1 p2
0 0 b80de5d13875 000000000000 000000000000
1 1 0376abec49b8 000000000000 000000000000
$ cd ..