[9.18] chg: ci: Set stricter limits for respdiff testing

Adjust the limit of maximum disagreements in respdiff results based on
recent pipeline results.

The respdiff and respdiff:asan seem to have almost identical results,
typically around 0.07 % of differences with ocassional spikes up to
around 0.11 %. Similar results are for respdiff:tsan, perhaps with more
common spikes with values up to around 0.12 %. Set the limit to 0.15 %
to allow for some tolerance due to network conditions, time of day etc.

The respdiff:third-party has a slightly higher disagreements average,
with typical values being around 0.12 %. Set the limit to 0.2 %.

Exceeding either of those values should be quite clear indication that
some resolution behaviour has changed, since the values appear to be
very stable within the newly configured limits.

Backport of MR !9950

Merge branch 'backport-nicki/ci-respdiff-limits-9.18' into 'bind-9.18'

See merge request isc-projects/bind9!9990

.gitlab-ci.yml

@@ -1514,7 +1514,7 @@ respdiff:
   variables:
     CC: gcc
     CFLAGS: "${CFLAGS_COMMON} -Og"
-    MAX_DISAGREEMENTS_PERCENTAGE: "0.5"
+    MAX_DISAGREEMENTS_PERCENTAGE: "0.15"
   script:
     - bash respdiff.sh -s named -q "${PWD}/100k_mixed.txt" -c 3 -w "${PWD}/rspworkdir" "${CI_PROJECT_DIR}" "/usr/local/respdiff-reference-bind/sbin/named"
 
@@ -1527,7 +1527,7 @@ respdiff:asan:
     CFLAGS: "${CFLAGS_COMMON} -Og -fsanitize=address,undefined"
     LDFLAGS: "-fsanitize=address,undefined"
     EXTRA_CONFIGURE: "--disable-dnsrps --without-jemalloc"
-    MAX_DISAGREEMENTS_PERCENTAGE: "0.5"
+    MAX_DISAGREEMENTS_PERCENTAGE: "0.15"
   script:
     - bash respdiff.sh -s named -q "${PWD}/100k_mixed.txt" -c 3 -w "${PWD}/rspworkdir" "${CI_PROJECT_DIR}" "/usr/local/respdiff-reference-bind/sbin/named"
 
@@ -1542,7 +1542,7 @@ respdiff:tsan:
     OPENSSL_CFLAGS: -I/opt/tsan/include
     OPENSSL_LIBS: -L/opt/tsan/lib -lssl -lcrypto
     EXTRA_CONFIGURE: "--disable-dnsrps --enable-pthread-rwlock --without-jemalloc PKG_CONFIG_PATH=/opt/tsan/lib/pkgconfig"
-    MAX_DISAGREEMENTS_PERCENTAGE: "0.5"
+    MAX_DISAGREEMENTS_PERCENTAGE: "0.15"
     TSAN_OPTIONS: "${TSAN_OPTIONS_DEBIAN}"
   script:
     - bash respdiff.sh -s named -q "${PWD}/100k_mixed.txt" -c 3 -w "${PWD}/rspworkdir" "${CI_PROJECT_DIR}" "/usr/local/respdiff-reference-bind/sbin/named"
@@ -1557,7 +1557,7 @@ respdiff-third-party:
   variables:
     CC: gcc
     CFLAGS: "${CFLAGS_COMMON} -Og"
-    MAX_DISAGREEMENTS_PERCENTAGE: "0.5"
+    MAX_DISAGREEMENTS_PERCENTAGE: "0.2"
   script:
     - bash respdiff.sh -s third_party -q "${PWD}/100k_mixed.txt" -c 1 -w "${PWD}/rspworkdir" "${CI_PROJECT_DIR}"