bump toolchain

kim-em · kim-em · commit a8093e7d6421 · 2026-02-02T00:40:00.000Z
diff --git a/lean-toolchain b/lean-toolchain
@@ -1 +1 @@
-leanprover/lean4:v4.28.0-rc1
+leanprover/lean4-pr-releases:pr-release-12263-a249288

Original file line number	Diff line number	Diff line change
`@@ -1 +1 @@`
`1`		`-leanprover/lean4:v4.28.0-rc1`
	`1`	`+leanprover/lean4-pr-releases:pr-release-12263-a249288`