DNM: see where the LIBCLANG_PATH set after Xtensa even after removing…

… it from GITHUB_ENV came from

.github/workflows/main.yml

@@ -24,7 +24,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        partition: ["1/20", "2/20", "3/20", "4/20", "5/20", "6/20", "7/20", "8/20", "9/20", "10/20", "11/20", "12/20", "13/20", "14/20", "15/20", "16/20", "17/20", "18/20", "19/20", "20/20"]
+        partition: ["1/1"]
 
     steps:
       - name: Check out repository code
@@ -64,6 +64,16 @@ jobs:
         with:
           buildtargets: esp32s3
 
+      - name: Investigate Xtensa mess
+        run: |
+          set -x
+          grep "" ~/.bashrc
+          grep "" ~/.profile
+          grep "" ~/exports
+          grep "" "${GITHUB_ENV}"
+          grep "" "${GITHUB_PATH}"
+          exit 1
+
       - name: Keep general build environment clean of Xtensa peculiarities
         # It also duplicates the path and does other things to the environment,
         # but setting LIBCLANG_PATH without setting CLANG_PATH breaks bindgen