test: stabilize test-remotefilelog-bgprefetch.t flaky output
When running the test suite with multiple processes, we often get flaky
outputs, like here: https://ci.octobus.net/job/MercurialPy2/274/console
```
- $TESTTMP/hgcache/master/packs/8f1443d44e57fec96f72fb2412e01d2818767ef2.histidx
- $TESTTMP/hgcache/master/packs/8f1443d44e57fec96f72fb2412e01d2818767ef2.histpack
- $TESTTMP/hgcache/master/packs/f4d50848e0b465e9bfd2875f213044c06cfd7407.dataidx
- $TESTTMP/hgcache/master/packs/f4d50848e0b465e9bfd2875f213044c06cfd7407.datapack
+ $TESTTMP/hgcache/master/11/f6ad8ec52a2984abaafd7c3b516503785c2072/1406e74118627694268417491f018a4a883152f0
+ $TESTTMP/hgcache/master/11/f6ad8ec52a2984abaafd7c3b516503785c2072/ef95c5376f34698742fe34f315fd82136f8f68c0
+ $TESTTMP/hgcache/master/39/5df8f7c51f007019cb30201c49e884b46b92fa/69a1b67522704ec122181c0890bd16e9d3e7516a
+ $TESTTMP/hgcache/master/95/cb0bfd2977c761298d9624e4b4d4c72a39974a/076f5e2225b3ff0400b98c92aa6cdf403ee24cca
+ $TESTTMP/hgcache/master/af/f024fe4ab0fece4091de044c58c9ae4233383a/bb6ccd5dceaa5e9dc220e0dad65e051b94f69a2c
```
Add some sleeps after `debugwaitonrepack` calls as it seems it needs some
extra time to cleanup.
Differential Revision: https://phab.mercurial-scm.org/D5960
--- a/tests/test-remotefilelog-bgprefetch.t Tue Feb 19 21:55:05 2019 -0800
+++ b/tests/test-remotefilelog-bgprefetch.t Thu Feb 14 14:36:16 2019 +0100
@@ -105,6 +105,7 @@
$ hg debugwaitonprefetch >/dev/null 2>%1
$ sleep 0.5
$ hg debugwaitonrepack >/dev/null 2>%1
+ $ sleep 0.5
$ find $CACHEDIR -type f | sort
$TESTTMP/hgcache/master/packs/6e8633deba6e544e5f8edbd7b996d6e31a2c42ae.histidx
$TESTTMP/hgcache/master/packs/6e8633deba6e544e5f8edbd7b996d6e31a2c42ae.histpack
@@ -193,6 +194,7 @@
$ hg debugwaitonprefetch >/dev/null 2>%1
$ sleep 1
$ hg debugwaitonrepack >/dev/null 2>%1
+ $ sleep 1
$ find $CACHEDIR -type f | sort
$TESTTMP/hgcache/master/packs/8f1443d44e57fec96f72fb2412e01d2818767ef2.histidx
$TESTTMP/hgcache/master/packs/8f1443d44e57fec96f72fb2412e01d2818767ef2.histpack
@@ -243,6 +245,7 @@
$ hg debugwaitonprefetch >/dev/null 2>%1
$ sleep 1
$ hg debugwaitonrepack >/dev/null 2>%1
+ $ sleep 1
# Ensure that file 'y' was prefetched - it was not part of the rebase operation and therefore
# could only be downloaded by the background prefetch