UI tweaks for GPT4All v3.0.0-rc2 (#2474)

* clickable link to get API key with hand-style mouse cursor
* remove "Force Metal" setting
* allow typing incorrect API keys (but don't accept them), add placeholder text

Signed-off-by: Jared Van Bortel <jared@nomic.ai>

gpt4all-chat/qml/ApplicationSettings.qml

@@ -420,7 +420,7 @@ MySettingsTab {
             Accessible.description: ToolTip.text
         }
 
-        MySettingsLabel {
+        /*MySettingsLabel {
             id: gpuOverrideLabel
             text: qsTr("Force Metal (macOS+arm)")
             Layout.row: 13
@@ -437,7 +437,7 @@ MySettingsTab {
             }
             ToolTip.text: qsTr("WARNING: On macOS with arm (M1+) this setting forces usage of the GPU. Can cause crashes if the model requires more RAM than the system supports. Because of crash possibility the setting will not persist across restarts of the application. This has no effect on non-macs or intel.")
             ToolTip.visible: hovered
-        }
+        }*/
 
         MySettingsLabel {
             id: updatesLabel