[data grid] Remove disableExtendRowFullWidth prop

[alexfauquette]

Shouldn't we fix disableExtendRowFullWidth too? Reading its description seems that we're supporting partially it = only removing the last border. If the description is correct, disableExtendRowFullWidth=false should behave like if the last column had flex=1.

mui-x/packages/grid/x-data-grid/src/models/props/DataGridProps.ts

Lines 163 to 166 in c746e61

	* If `true`, rows will not be extended to fill the full width of the grid container.
	* @default false
	*/
	disableExtendRowFullWidth: boolean;

Currently, it gives the impression that the row is extending the full width, but once the cell is clicked I see its true width.

Changing the way disableExtendRowFullWidth works can be a breaking change, it depends on how we see its behavior.

Originally posted by @m4theushw in #4224 (review)

Observations

To do it, we should care about the column resizing which implies two levels of modification:

1. In initialization the last visible column with is replaced by flex 1, such that its width will fill the remaining space
2. When resizing the last column is updated to be sure that the last column fills the space. This brings questions about how can new modify the last column width

[flaviendelangle]

Maybe put a shorter issue title 😄

[cherniavskii]

We came to the conclusion that we can remove the disableExtendRowFullWidth prop because it's confusing and doesn't seem to provide much value.