Fix Mikrotik / Mikrotik 7 src-address separator

[HomesONE]

Problem

When source-interface-id is configured as an IP address (rather than an interface name), build_ping() and build_traceroute() in mikrotik.php and the parallel methods in mikrotik7.php emit:

```php
$cmd->add('src-address=');
$cmd->add($this->get_source_interface_id('ipv4'));
```

CommandBuilder::__toString() joins added elements with its separator (default single space), so the resulting RouterOS command is:

```
/tool/ping ... src-address= 1.2.3.4 ...
```

with a space between = and the address — RouterOS rejects this with a syntax error. The interface variant on the else branch already concatenates correctly:

```php
$cmd->add('interface='.$this->get_source_interface_id());
```

Fix

Move the src-address= prefix into the same add() call as the value, matching the pattern already used for address= and interface=:

```php
if (match_ipv6($parameter)) {
$cmd->add('src-address='.$this->get_source_interface_id('ipv6'));
} else {
$cmd->add('src-address='.$this->get_source_interface_id('ipv4'));
}
```

Affected configs

Any Mikrotik (RouterOS 6) or Mikrotik 7 router with source-interface-id set to an IPv4 or IPv6 literal. Configs using an interface name (the more common case) are unaffected.

Smoke test

Before:
```
/tool/ping count=1 address=8.8.8.8 src-address= 10.0.0.1
syntax error (line 1 column 56)
```

After:
```
/tool/ping count=1 address=8.8.8.8 src-address=10.0.0.1
SEQ HOST SIZE TTL TIME STATUS
0 8.8.8.8 56 56 5ms
```