doc: use full path /usr/bin/pass in example for option sec.crypt.passphrase_command

doc/it/includes/autogen_user_commands.it.adoc

@@ -1885,7 +1885,7 @@ Examples:
   set a passphrase:
     /secure passphrase this is my passphrase
   use program "pass" to read the passphrase on startup:
-    /set sec.crypt.passphrase_command "pass show weechat/passphrase"
+    /set sec.crypt.passphrase_command "/usr/bin/pass show weechat/passphrase"
   encrypt freenode SASL password:
     /secure set freenode mypassword
     /set irc.server.freenode.sasl_password "${sec.data.freenode}"

doc/it/includes/autogen_user_options.it.adoc

@@ -17,7 +17,7 @@
 ** valore predefinito: `+sha256+`
 
 * [[option_sec.crypt.passphrase_command]] *sec.crypt.passphrase_command*
-** descrizione: pass:none[read the passphrase from the output of this system command (only the first line is used and it must not contain any extra character); this option is used only when reading file sec.conf and if the environment variable "WEECHAT_PASSPHRASE" is not set (the environment variable has higher priority); example with password-store: "pass show weechat/passphrase"]
+** descrizione: pass:none[read the passphrase from the output of this system command (only the first line is used and it must not contain any extra character); this option is used only when reading file sec.conf and if the environment variable "WEECHAT_PASSPHRASE" is not set (the environment variable has higher priority); example with password-store: "/usr/bin/pass show weechat/passphrase"]
 ** tipo: stringa
 ** valori: qualsiasi stringa
 ** valore predefinito: `+""+`

doc/it/weechat_user.it.adoc

@@ -2466,7 +2466,7 @@ the passphrase instead of having to type it manually on WeeChat startup. +
 For example with password-store (command `pass`):
 
 ----
-/set sec.crypt.passphrase_command "pass show weechat/passphrase"
+/set sec.crypt.passphrase_command "/usr/bin/pass show weechat/passphrase"
 ----
 
 The program may ask you unlock your GPG key or enter another passphrase to