fix(searchQueryBuilder): Add null check to formatFilterValue to prevent TypeError

[sentry]

Addresses JAVASCRIPT-39R3, a TypeError occurring in formatFilterValue when token is null. The root cause was that formatFilterValue was called with a null token argument, due to the call site using item.value! (a non-null assertion) which bypasses runtime null checks. The formatFilterValue function lacked a runtime null check for its token argument, leading to a crash when accessing token.type. This fix adds a null guard at the beginning of formatFilterValue to return an empty string if token is null, preventing the TypeError.

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Fixes JAVASCRIPT-39R3

_{Comment @sentry <feedback> on this PR to have Autofix iterate on the changes.}