Keep a List of Feedback
It's really easy to miss an opportunity to share positive feedback with your teammates. It might be that you don't have a habit of pointing out great work and therefore struggle to identify those opportunities in the first place. It might be that you are able to identify moments of excellence but you forget to bring them up the next time you interact with your teammates.
Positive feedback makes us learn faster. Positive feedback helps us be more open to ideas that challenge our thinking. Positive feedback can elevate your team in a way that negative criticism can't (if you are skeptical about the value of positive feedback, consider reading Marcus Buckingham and Ashley Goodall's article The Feedback Fallacy).
Making sure that positive feedback gets shared inside your team doesn't have to be solely your team leader's responsibility. You can also make it your job to highlight excellence.
Start keeping a list of the great outcomes you see in your colleague's work. Point out those outcomes to your colleague in the next retrospective or at the end of the week. Keep collecting items on that list and keep going through the items regularly. You'll start helping others with their professional growth and you'll probably start experiencing a positive change in how you view the work of others.
When I worked at Kisko Labs we used to share "thank you" messages to our colleagues every Friday. It was an opportunity to thank each other for the help we received during the week, great moments we got to share with each other, and any efforts from our colleagues to make the work environment better.
Since this was a company-wide practice and there were email reminders sent out to people to share their thanks, those messages of gratitude got written. The environment supported and nudged us to keep finding reasons to thank each other. I found myself writing to-dos for my thank you messages throughout the week so I wouldn't forget them on Friday.
You and I might not be nudged to share positive feedback in such a systematic way. Therefore, it's our responsibility to build those habits for ourselves. Ideally you would be able to highlight great work as soon as you see it. But if this is something you're not used to, you might find supporting tools helpful. Consider the list.