Exclusion number in VANDERWAALS is ignored

The code to generate exclusions uses the nexcl value in the ELECTROSTATICS for both that and VANDERWAALS
```
auto myItype = InteractionType::ELECTROSTATICS;
if (!ffOption(*pd, myItype, "nexcl", &nexcl))
{
msghandler->fatal(gmx::formatString("The number of exclusions is not specified for %s in %s", interactionTypeToString(myItype).c_str(), pd->filename().c_str()));
}
auto exclusions = generateExclusions(msghandler, nexcl);
makePairs(msghandler, pd, InteractionType::VDW, exclusions);
makePairs(msghandler, pd, InteractionType::ELECTROSTATICS, exclusions);
```
so if the nexcl are different, the result would be incorrect.

Locate the exclusion-generation code containing the shown nexcl lookup and read how interaction types are handled around generateExclusions and makePairs. Compare the VANDERWAALS and ELECTROSTATICS configuration paths, then verify that differing nexcl values produce the intended exclusions for each interaction type.

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