Should rename treeSupportsFind to listSupportsFind

[bpasero]

I think this came up during the standup today, why is the context key called treeSupportsFind and not listSupportsFind?

//cc @alexdima

[alexdima]

This context key came in quite late via a fix -- #156637 . I noticed this standing out because of the default keybindings which seem to mix things up:

{ "key": "f3",                    "command": "list.find",
                                     "when": "listFocus && treeSupportsFind" },
{ "key": "cmd+f",                 "command": "list.find",
                                     "when": "listFocus && treeSupportsFind" },

Giving this a candidate in case we want to align the context key before shipping stable

[bpasero]

From e8ee2cf