setup-miniconda: correct channel prio

pypdfium2-team should be prioritized over bblanchon (not that it
currently matters, though)
See
https://github.com/conda-incubator/setup-miniconda#example-4-conda-options
for how this option is applied. Top means highest priority.

.github/workflows/conda.yaml

@@ -47,7 +47,7 @@ jobs:
         with:
           auto-update-conda: true
           python-version: ${{ inputs.py_version }}
-          channels: bblanchon,pypdfium2-team
+          channels: pypdfium2-team,bblanchon
           channel-priority: strict
 
       - name: Prepare
@@ -128,12 +128,13 @@ jobs:
 
     steps:
 
+      # FIXME custom channels probably not necessary here
       - name: Miniconda setup
         uses: conda-incubator/setup-miniconda@v2
         with:
           auto-update-conda: true
           python-version: ${{ matrix.py }}
-          channels: bblanchon,pypdfium2-team
+          channels: pypdfium2-team,bblanchon
           channel-priority: strict
 
       - name: Install deps

README.md

@@ -60,7 +60,7 @@ pypdfium2 includes helpers to simplify common use cases, while the raw PDFium/ct
       uses: conda-incubator/setup-miniconda@v2
       with:
         # ... your options
-        channels: bblanchon,pypdfium2-team
+        channels: pypdfium2-team,bblanchon
         channel-priority: strict
     ```
     This is just a suggestion, you can also call `conda config` manually, or pass channels on command basis using `-c`, as discussed above.