Less-than filter excludes all rows when erased manually and another filter is still applied on the same column

[mage-eag]

This behaviour is reproducible on the filtering tutorial :

1. Filter the "Age" column on values greater than 1
2. Filter the same column on values lesser than 30
3. Erase the "less than" field manually (not using the dedicated button)

Result : all the rows are now filtered out.

The reason seems to be that the term value is not reset to null or undefined when the corresponding field is erased by hand, but is still taken into account because another filter on the same column still has a "valid" term value.

I managed to fix this by testing for an empty string when number values are involved, but I'm not sure at all whether this is a convenient solution, or if this could bring unwanted side-effects.

Please let me know what are your thoughts about it, and whether I can create a PR with the possible fix.

[alam123]

I have already raised this issue and submitted a pull request.

#3923
#4012

[mage-eag]

Oops sorry, I had seen your PR but funnily did not make the connection .. thanks, will start using it right away :)