Update mamba-org/setup-micromamba to v2

[hameerabbasi]

What type of PR is this? (check all applicable)

• 💾 Refactor
• 🪄 Feature
• 🐞 Bug Fix
• 🔧 Optimization
• 📚 Documentation
• 🧪 Test
• 🛠️ Other

Related issues

• Related issue #
• Closes #

Checklist

• Code follows style guide
• Tests added
• Documented the changes

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Please explain your changes below.

[codspeed-hq]

CodSpeed Performance Report

Merging #788 will degrade performances by 54.44%

_{Comparing update-mm-action (4233f98) with main (db60537)}

Summary

❌ 8 regressions
✅ 332 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	main	update-mm-action	Change
❌	test_index_fancy[side=100-rank=1-format='coo']	643.5 µs	1,412.5 µs	-54.44%
❌	test_index_slice[side=100-rank=2-format='gcxs']	2.2 ms	2.7 ms	-18.43%
❌	test_elemwise[f=<built-in function add>-backend='Finch'-side=1000]	1.5 ms	1.8 ms	-16.62%
❌	test_elemwise[f=<built-in function add>-backend='Finch'-side=100]	713.7 µs	1,009.9 µs	-29.33%
❌	test_elemwise[f=<built-in function add>-backend='Finch'-side=500]	882.4 µs	1,175.8 µs	-24.96%
❌	test_elemwise[f=<built-in function mul>-backend='Finch'-side=1000]	736.4 µs	1,062.7 µs	-30.71%
❌	test_elemwise[f=<built-in function mul>-backend='Finch'-side=100]	694 µs	1,020.3 µs	-31.98%
❌	test_elemwise[f=<built-in function mul>-backend='Finch'-side=500]	713.3 µs	1,039 µs	-31.35%

[hameerabbasi]

Superceded by #790