CI: build in ci, more streamlined toolchain

Reviewed-on: #2
Co-authored-by: Stepan Usatiuk <stepan@usatiuk.com>
Co-committed-by: Stepan Usatiuk <stepan@usatiuk.com>

toolchain_scripts/grub.sh

@@ -17,7 +17,7 @@ mkdir -p prefix
 
 if [ ! -d "grub-2.06" ]; then
     wget https://ftp.gnu.org/gnu/grub/grub-2.06.tar.xz
-    tar xvf grub-2.06.tar.xz
+    tar xf grub-2.06.tar.xz
     rm grub-2.06.tar.xz
 fi
 
@@ -43,4 +43,8 @@ export PATH="$PREFIX/bin:$PATH"
 make -j$(nproc)
 make install
 
+cd ..
+rm -rf build
+rm -rf grub-2.06
+
 touch -m ../done