And yes, I think it does signify the way both characters develop over the course of the show. Garak is teaching Bashir, but Bashir is teaching Garak at the same time. They practically swap places. Bashir becomes suspicious, distrustful, involved in shady dealings and nefarious secret organisations. Garak becomes one of the team, working for the greater good, a trusted friend and confidant, a righter of wrongs.
I wouldn't go that far. The only reason Garak really became "one of the team" was because they were in a war where his skills would be useful. I think the only thing they trusted was his dislike towards the Dominion was genuine.
Bashir did become more suspicious and distrustful and involved in shady dealings. But that last part really wasn't his fault as he was targeted by 31 and not the other way around.
Did they rub off on each other at least a bit? Sure. I don't think they fundamentally changed the core values of each other though.