condition extractor -- dumping partial dumps

Make the `extractor` able to dump function constraints right after the analysis terminates.

Add an additional flag to the tool (e.g., `--partial_dump` ??).

Probably add something like
```C
if (OutputType == OutType::txt) {
FunctionConditionsSet::storeIntoTextFile(
fun_cond_set, OutputFile, verbose >= Verbosity::v1);
} else if (OutputType == OutType::json) {
FunctionConditionsSet::storeIntoJsonFile(
fun_cond_set, OutputFile, verbose >= Verbosity::v1);
} else if (OutputType == OutType::stdo) {
SVFUtil::outs() << fun_cond_set.toString(verbose >= Verbosity::v1);
}
```
at around this [line](https://github.com/HexHive/libfuzz/blob/main/condition_extractor/src/extractor.cpp#L743).

Then, add a cleaning method for `FunctionConditionSet` ([here](https://github.com/HexHive/libfuzz/blob/00e055bdc5693e5b389fdb383193812c98da69ec/condition_extractor/src/AccessType.h#L840))

Partial results should be stored in a dedicated folder (another flag? a tmp folder?) and then grouped together through a dedicated tool (e.g., a python script to be invoked afterward).