Pin conda <25.7 to fix Windows build

Summary:
🤖 This diff was automatically generated by myclaw_faiss_monitor

conda 25.7.0 was released today and broke conda-build 25.3.1's plugin
registration. When conda 25.7.0 is installed, the `conda build` subcommand
is no longer recognized, even though conda-build is installed in the same
environment. Root cause: conda-build 25.3.1 was released before conda 25.7.0
and its plugin entry point is incompatible with conda 25.7.0's plugin loader.

Fix: change `<=25.07` to `<25.7` to exclude conda 25.7.0 until conda-build
is updated to support it.

The previous constraint `<=25.07` treated 25.07 and 25.7.0 as equivalent
(PEP 440), so conda 25.7.0 was pulled in. The new constraint `<25.7` pins
below the broken release.

Differential Revision: D103589106

Author: mdouze

.github/actions/build_conda/action.yml

@@ -43,7 +43,7 @@ runs:
       run: |
         # Ensure starting packages are from conda-forge.
         conda list --show-channel-urls
-        conda install -y -q "conda!=24.11.0,<=25.07"
+        conda install -y -q "conda!=24.11.0,<25.7"
         conda install -y -q "conda-build=25.3.1" "liblief=0.14.1"
     - name: Enable anaconda uploads
       if: inputs.label != ''