tighten fmt in libmamba

recipe/patch_yaml/mamba.yaml

@@ -1,3 +1,4 @@
+# yaml-language-server: $schema=../patch_yaml_model.json
 # from this code
 # if (
 #     subdir in ["linux-64", "linux-aarch64", "linux-ppc64le"]
@@ -141,3 +142,13 @@ then:
   - replace_depends:
       old: conda >=23.9,<24
       new: conda >=23.9,<23.11.0
+---
+# fmt 10.2.0 breaks libmamba on Windows
+# https://github.com/conda-forge/fmt-feedstock/pull/39
+if:
+  name: libmamba
+  timestamp_lt: 1704218331614
+then:
+  - tighten_depends:
+      name: fmt
+      upper_bound: "10.2.0"