Fix base-path handling in key insert (#7775)

This fixes the handling of base-path when using `key insert`. Before
the base-path wasn't setup correctly, as done when starting a node. This
resulted in putting the keys into the wrong directory. This pr fixes
this by creating the correct base-path/config dir for the keystore.
Besides that it also removes the insert command from `subkey` as it
doesn't make that much sense. If requested, we could bring it back later.

substrate/primitives/core/src/crypto.rs

@@ -1052,6 +1052,7 @@ impl From<KeyTypeId> for u32 {
 
 impl<'a> TryFrom<&'a str> for KeyTypeId {
 	type Error = ();
+
 	fn try_from(x: &'a str) -> Result<Self, ()> {
 		let b = x.as_bytes();
 		if b.len() != 4 {