Is it safe to remove debconf cache files in isar system

[<Venkata.Pyla@toshiba-tsip.com>]

Hi,

I am working to fix some reproducible build failures in isar system, as part of this I wanted to know some ideas to fix it.

I am checking the reproducible failures as below:
 $ cd isar
 $ . isar-init-build-env build1 && bitbake mc:qemuamd64-buster-tgz:isar-image-base
 $ . isar-init-build-env build2 && bitbake mc:qemuamd64-buster-tgz:isar-image-base
 $ mkdir -p rootfs1 rootfs2
 $ tar -xzvf ./build1/tmp/deploy/images/qemuamd64/isar-image-base-debian-buster-qemuamd64.tar.gz -C ./rootfs1/
 $ tar -xzvf ./build2/tmp/deploy/images/qemuamd64/isar-image-base-debian-buster-qemuamd64.tar.gz -C ./rootfs2/
 $ rsync -nrclv ./rootfs1/ ./rootfs2/ > difference.txt

Below is one reproducible problem I picked:
In debconf db file the contents were different after two subsequent builds,

Part of the debconf db file where the difference is found (/var/cache/debconf/config.dat)
Build1:
Name: ucf/changeprompt
Template: ucf/changeprompt
Value: keep_current
Owners: ucf
Variables:
 BASENAME = locale.nopurge
 FILE = /etc/locale.nopurge
 NEW = /etc/locale.nopurge.29308

Build2:
Name: ucf/changeprompt
Template: ucf/changeprompt
Value: keep_current
Owners: ucf
Variables:
 BASENAME = locale.nopurge
 FILE = /etc/locale.nopurge
 NEW = /etc/locale.nopurge.19132

The probable solution I am thinking of is:
1. remove the debconf cache files (rm -f /var/cache/debconf/*)
2. Fix the debconf in such a way it generates same package configuration on every build

The first solution is easy, but I am worried if those package configuration files maybe required in future when the package is updating
The second solution would need more investigation at debconf package side. 

Any ideas or suggestion would be very grateful.

Thanks,
Venkata.