fix: correct rattler-build condition syntax for osx and win build scripts

Author: salim-b

recipe/recipe.yaml

@@ -20,9 +20,11 @@ build:
         then:
           # cf. https://github.com/stakpak/agent/blob/main/cli/src/main.rs#L17
           - cargo auditable install --locked --no-track --bins --features jemalloc --root ${{ PREFIX }} --path cli
-        else if: unix
+      - if: osx
+        then:
           - cargo auditable install --locked --no-track --bins --root ${{ PREFIX }} --path cli
-        else:
+      - if: win
+        then:
           - cargo auditable install --locked --no-track --bins --root %LIBRARY_PREFIX% --path cli
       - cargo-bundle-licenses --format yaml --output ./THIRDPARTY.yml