[3.15] gh-145098: Use macos-26[-intel] instead of `macos-15[-intel]…
#6961
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| 1h 0m 17s | |
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| 16m 26s | |
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| 4m 51s | |
| 10m 0s | |
| 27m 39s | |
| 5h 40m 5s |