UI: Disable stream encoder setting in simple output with active output

We disable the stream encoder setting in Advanced Output Mode when an
output is active, so let's also disable the stream encoder setting in
Simple Output Mode when an output is active.

UI/forms/OBSBasicSettings.ui

@@ -1378,7 +1378,7 @@
                   <number>0</number>
                  </property>
                  <item>
-                  <widget class="QGroupBox" name="groupBox_8">
+                  <widget class="QGroupBox" name="simpleStreamingGroupBox">
                    <property name="sizePolicy">
                     <sizepolicy hsizetype="Preferred" vsizetype="Maximum">
                      <horstretch>0</horstretch>
@@ -1549,7 +1549,7 @@
                      <widget class="QComboBox" name="simpleOutStrEncoder"/>
                     </item>
                     <item row="1" column="0">
-                     <widget class="QLabel" name="simpleOutRecEncoderLabel_2">
+                     <widget class="QLabel" name="simpleOutStrEncoderLabel">
                       <property name="text">
                        <string>Basic.Settings.Output.Encoder</string>
                       </property>

UI/window-basic-settings.cpp

@@ -2064,6 +2064,8 @@ void OBSBasicSettings::LoadOutputSettings()
 	if (obs_video_active()) {
 		ui->outputMode->setEnabled(false);
 		ui->outputModeLabel->setEnabled(false);
+		ui->simpleOutStrEncoderLabel->setEnabled(false);
+		ui->simpleOutStrEncoder->setEnabled(false);
 		ui->simpleRecordingGroupBox->setEnabled(false);
 		ui->replayBufferGroupBox->setEnabled(false);
 		ui->advOutTopContainer->setEnabled(false);