[sr-dev] [kamailio/kamailio] config file: defexps not working in modparam (Issue #3631)

### Description

When an ID is defined using `!#defexps` it cannot be used in modparam

### Troubleshooting

``` #!define TEST1 "key=s:value" ## this works modparam("pv", "varset", TEST1)

# in shell: export TEST2='key=s:value' #!defenvs TEST2 modparam("pv", "varset", TEST2)

# this does not work #!defexps TEST3 "key=s:value" modparam("pv", "varset", TEST3)

0(2437437) CRITICAL: <core> [core/cfg.y:3900]: yyerror_at(): parse error in config file kamailio.cfg, line 85, column 26-32: syntax error

```

#### Reproduction

* in config file, define ID with `#!defexps` then use in `modparam()`

#### Debugging Data