Revert "feat(tools): use ESP_PYTHON during install"

This change seems to be causing problems on macos. Let's revert it
for now and investigate.

This reverts commit 6a7a7317f22b5b7b46c5c44138f4046064461ee8.

tools/detect_python.fish

@@ -5,10 +5,9 @@
 set OLDEST_PYTHON_SUPPORTED_MAJOR 3
 set OLDEST_PYTHON_SUPPORTED_MINOR 7
 
-set -q ESP_PYTHON; or set PYLIST python3 python python3.7 python3.8 python3.9 python3.10 python3.11 python3.12
-set -q ESP_PYTHON; or set -x ESP_PYTHON python
+set -x ESP_PYTHON python
 
-for p_cmd in $PYLIST;
+for p_cmd in python3 python python3.7 python3.8 python3.9 python3.10 python3.11 python3.12;
     $p_cmd --version >/dev/null 2>&1; or continue
     echo "Checking \"$p_cmd\" ..."
 

tools/detect_python.sh

@@ -10,10 +10,9 @@
 OLDEST_PYTHON_SUPPORTED_MAJOR=3
 OLDEST_PYTHON_SUPPORTED_MINOR=7
 
-PYLIST=${ESP_PYTHON:-python3 python python3.7 python3.8 python3.9 python3.10 python3.11 python3.12}
-ESP_PYTHON=${ESP_PYTHON:-python}
+ESP_PYTHON=python
 
-for p_cmd in $PYLIST; do
+for p_cmd in python3 python python3.7 python3.8 python3.9 python3.10 python3.11 python3.12; do
     $p_cmd --version >/dev/null 2>&1 || continue
     echo "Checking \"$p_cmd\" ..."