How to increase table raw height by 0.1?

It can be scripted

and you can add a keyboard shortcut to each script to do it with a key command

Increase by .1

var doc = app.activeDocument;

if (doc.selection.length === 1 && doc.selection[0].constructor.name === "Cell") {
  var selectedRow = doc.selection[0].parentRow;
  var currentHeight = selectedRow.height;
  selectedRow.height = currentHeight + 0.1;
} else {
  alert("Please select a single table row before running this script.");
}

Decrease by .1

var doc = app.activeDocument;

if (doc.selection.length === 1 && doc.selection[0].constructor.name === "Cell") {
  var selectedRow = doc.selection[0].parentRow;
  var currentHeight = selectedRow.height;
  selectedRow.height = currentHeight - 0.1;
} else {
  alert("Please select a single table row before running this script.");
}

 or just double click the scripts