cache/predict: tweak *when* an RR is expiring

1% TTL is just too little when used for refreshing.
Even 50% would mean doing at most double work than necessary,
so let's have this compromise of ~7% TTL.
16 jobs for expiring in 10 minutes and 54 seconds (queued for 14 seconds)
latest
Status Job ID Name Coverage
  Build
passed build:clang:linux:amd64 #109446
docker linux amd64

00:00:30

passed build:linux:amd64 #109445
docker linux amd64

00:00:27

 
  Test
passed deckard:linux:amd64 #109476
docker linux amd64

00:06:00

passed doc #109452
docker

00:00:36

passed installcheck:linux:amd64 #109451
docker linux amd64

00:00:49

passed installcheck:valgrind:linux:amd64 #109454
docker linux amd64

00:01:17

passed lint:c #109448
docker

00:01:58

failed lint:clang-scan-build #109449
docker allowed to fail

00:00:56

passed lint:lua #109447
docker

00:00:28

passed respdiff:iter:tcp:linux:amd64 #109457
docker linux amd64

00:03:58

passed respdiff:iter:tls:linux:amd64 #109458
docker linux amd64

00:03:50

passed respdiff:iter:udp:linux:amd64 #109456
docker linux amd64

00:02:37

passed test:linux:amd64 #109450
docker linux amd64

00:00:44

passed test:linux:amd64:valgrind #109455
docker linux amd64

00:00:57

failed deckard:linux:amd64 #109453
docker linux amd64

00:00:51

 
  Coverage
passed coverage #109459
docker linux amd64

00:00:19

70.3%
 
Name Stage Failure
failed
lint:clang-scan-build Test
                                             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
5 warnings generated.
CCLD daemon/kresd
scan-build: 22 bugs found.
scan-build: Run 'scan-view /builds/knot/knot-resolver/scan-results/2018-02-15-093951-14-1' to examine bug reports.
Uploading artifacts...
scan-results: found 27 matching files
Uploading artifacts to coordinator... ok
id=109449 responseStatus=201 Created token=9ujkA9fj
ERROR: Job failed: exit code 1