fix: do not round up to int percents in conclusions and recommendations.

Description

The output of percents values in the Conclusions and Recommendations section of several reports has been done with a round up to int value. It has limited accuracy of values.

The format of percentage output before the fix:%.0f. The format of percentage output after the fix:%.2f.

Related issue

By usage remarks.

Examples

Before:

`idx01`: size 7.65 MiB, can be reduced 326.33 times, by ~7.63 MiB (~100%)

After:

`index_1`: size 373.29 MiB, can be reduced 7.68 times, by ~324.71 MiB (~96.99%)