Open new entry in changelog

As explained at[1], piuparts job setup local repository with packages
just built. If their version is equal to version in archives, job will
fail with "Sources disagree on hashes of supposely identical version"
error. So, to keep CI clean, it is necessary to create new changelog
entry after release.

 [1] salsa-ci-team/pipeline#46 (comment 80587)
8 jobs for master in 28 minutes and 27 seconds (queued for 2 seconds)
latest
Status Job ID Name Coverage
  Build
passed #279738
build

00:03:57

 
  Test
passed #279743
autopkgtest

00:03:09

failed #279744
blhc

00:01:32

passed #279742
lintian

00:02:37

passed #279745
piuparts

00:06:01

failed #279741
reprotest

00:03:55

passed #279740
test-build-all

00:03:28

passed #279739
test-build-any

00:03:44

 
Name Stage Failure
failed
blhc Test
Skipping Git submodules setup
Downloading artifacts for build (279738)...
Downloading artifacts from coordinator... ok id=279738 responseStatus=200 OK token=WSwATFzg
Authenticating with credentials from job payload (GitLab Registry)
$ blhc --debian --line-numbers --color ${WORKING_DIR}/*.build || [ $? -eq 1 ]
142:
NONVERBOSE BUILD: \ echo libtool --mode=link --silent $tag `head -n 1 conf-ld` '-o "$lib" -rpath' `head -n 1 conf-lib` -version-info `head -n 1 LIBVERSION` '${1+"$@"}'
149:
NONVERBOSE BUILD: \ echo exec libtool --mode=compile --silent $tag `head -n 1 conf-cc` -I. "-I'include/bglibs'" "-I'include'" '-o ${base}.lo -c $source ${1+"$@"}'
627:
NONVERBOSE BUILD: \ echo exec libtool --mode=link --silent $tag `head -n 1 conf-ld` -L. '-o "$main" "$main.o" ${1+"$@"}'
ERROR: Job failed: exit code 1
failed
reprotest Test
        if ( cleanup ); then :; else echo >&2 "cleanup failed with exit code $?"; fi;
fi
exit $__x
fi" failed with status 2
Uploading artifacts...
/builds/debian/bglibs/debian/output/reprotest: found 8 matching files
/builds/debian/bglibs/debian/output/reprotest.log: found 1 matching files

Uploading artifacts to coordinator... ok
id=279741 responseStatus=201 Created token=hYKVgPax
ERROR: Job failed: exit code 1