jwt: let Geth generate secret by itself

Using `password_hash` doesn't work as the value has to be hex encoded.

Signed-off-by: Jakub Sokołowski <jakub@status.im>

defaults/main.yml

@@ -55,7 +55,7 @@ geth_authrpc_enabled: true
 geth_authrpc_addr: '127.0.0.1'
 geth_authrpc_port: 8551
 geth_authrpc_vhosts: '{{ geth_rpc_vhosts }}'
-geth_authrpc_jwtsecret: '{{ geth_service_name | password_hash("sha512", (inventory_hostname|hash("sha1"))[0:16], rounds=5000) }}'
+#geth_authrpc_jwtsecret: '0x64charHexEncodedSecretToken'
 geth_authrpc_jwtsecret_file: '{{ geth_cont_vol }}/keys/jwtsecret'
 
 # Sync mode: full, fast, light, snap

tasks/generate.yml

@@ -103,6 +103,7 @@
     group: 'docker'
 
 - name: Geth | Create JWT secret file
+  when: geth_authrpc_jwtsecret is defined
   copy:
     dest: '{{ geth_authrpc_jwtsecret_file }}'
     content: '{{ geth_authrpc_jwtsecret | mandatory }}'