Is it appropriate to mention personal lessons learned in the defense presentation? I have to defend my master's thesis in the field of computer science in about one week.

Of course I will put the main focus of the presentation on the thesis itself, i.e. the research question, the methodology and the results.

But besides the evident results, I also feel that writing the thesis thought me some really important personal lessons. For the first time in my student career I think I got a feeling about what research really is about to be - Spending long hours in front of a problem, constantly discarding and revising ideas while trying to stay positive when coping with setbacks and self-doubt. That I eventually finished the thesis despite all struggles was a very positive experience for me and somehow I'd like to mention that in the defense.

I know from other answers on this site that such things seem to depend a lot on the faculty. However, the guidelines of my faculty only specify the hard facts of the defense such as number of senate members, the schedule and the like.

So I wondered, if I sum up my personal lessons and experiences in 1 or 2 slides, would you as a senate member feel that this is appropriate or something that totally is out of place within the context of a defense?
A bachelor's or master's degree is about the knowledge that you have gained. A Ph.D., on the other hand, is about the knowledge that you have contributed to humanity.  As such, the defense is not really about you: it's about your work, and you need to treat it as such.  Think about the other high-level scientific talks that you have seen (or given), and treat your defense in exactly the same way.

That's not to say that you can't weave in personal experiences or anecdotes if they make sense as part of the presentation of the technical content.  Some of the best talks that I have ever seen have a component of the personal in them.  The important distinction is that any use of the personal should serve to illuminate and illustrate the scientific point, rather than standing apart and distracting from it.