Revert default BTT STM32F103 environment (#16006)

buildroot/share/tests/STM32F103RC_bigtree_USB-tests

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+#
+# Build tests for STM32F103RC Bigtreetech (SKR Mini v1.1)
+#
+
+# exit on first failure
+set -e
+
+#
+# Build with the default configurations
+#
+restore_configs
+opt_set MOTHERBOARD BOARD_BIGTREE_SKR_MINI_V1_1
+opt_set SERIAL_PORT 1
+opt_set SERIAL_PORT_2 -1
+exec_test $1 $2 "Bigtreetech SKR Mini v1.1 - Basic Configuration"
+
+# clean up
+restore_configs