Description of problem:

After migrating a RHEL 7 system sar data files (historic data) are not longer read by new sysstat version in RHEL 8.

"Current sysstat version cannot read the format of this file" (please see attached screenshot).

It'd be ideal to add a low rating warning message in leapp-report.txt file stating a conversion of all sa/sar files must be peformed after the migration because sysstat on RHEL 8 won't be able to read historic data.

Possible hint could be pointing to KCS https://access.redhat.com/solutions/5240511.

Version-Release number of selected component (if applicable):
leapp-repository-0.14.0-4.el7_9.noarch

How reproducible:
100%

Steps to Reproduce:
1. Install sysstat on RHEL 7
yum install -y sysstat

2. Run sa1 command to collect and store binary data of system's activity.
/usr/lib64/sa/sa1 1 1

3. Read the sa## file generated

sar -f sa15
Linux 3.10.0-1160.el7.x86_64 (rhel79.domain.net) 07/15/2022 x86_64 (1 CPU)

03:13:18 PM CPU %user %nice %system %iowait %steal %idle
03:13:19 PM all 1.20 0.00 1.20 0.00 0.00 97.60
03:13:20 PM all 1.25 0.00 1.25 0.00 0.00 97.50
Average: all 1.21 0.00 1.21 0.00 0.00 97.57

4. Perform a migration RHEL 7 -> RHEL 8

5. Once in RHEL 8 try to read sa15 using sar command.

[root@rhel86 vagrant]# sar -f sa15
Invalid system activity file: sa15
File created by sar/sadc from sysstat version 10.1.5
Current sysstat version cannot read the format of this file (0x2171)

Actual results:
There isn't any low rate message warning about this.

Expected results:
A low risk warning message with a hint steps about how to convert the sa files.

Additional info:
Maybe including kcs https://access.redhat.com/solutions/5240511 in hints for further information.