fix: source code tips contract-storage.adoc (#1464)

Author: qvkare

components/Starknet/modules/architecture-and-concepts/pages/smart-contracts/contract-storage.adoc

@@ -11,7 +11,7 @@ The contract's storage is a persistent storage space where you can read, write,
 
 The basic function for writing to storage writes, value to key is:
 
-[source,js]
+[source,cairo]
 ----
 storage_write_syscall(address_domain, address, value)
 ----
@@ -24,7 +24,7 @@ address is determined from the variable's name and keys.
 
 Both `storage_read` and `storage_write` are system calls that can be imported by adding the line:
 
-[source,javascript]
+[source,cairo]
 ----
 use starknet::syscalls::storage_read_syscall;
 use starknet::syscalls::storage_write_syscall;
@@ -68,5 +68,3 @@ struct Storage {
     allowances: LegacyMap::<(ContractAddress, ContractAddress), u256>,
 }
 ----
-
-