Bug 1840969 - Add title for homepage default browser info card

Title for the card info to set Firefox as default browser was
missing, "Switch your default browser" is the title now, to
match with iOS.

app/messaging-evergreen-messages.fml.yaml

@@ -25,6 +25,7 @@ import:
         - value:
             messages:
               default-browser:
+                title: default_browser_experiment_card_title
                 text: default_browser_experiment_card_text
                 surface: homescreen
                 action: "MAKE_DEFAULT_BROWSER"

app/src/main/java/org/mozilla/fenix/compose/MessageCard.kt

@@ -208,7 +208,7 @@ private fun MessageCardPreview() {
         ) {
             MessageCard(
                 messageText = stringResource(id = R.string.default_browser_experiment_card_text),
-                titleText = stringResource(id = R.string.bookmark_empty_title_error),
+                titleText = stringResource(id = R.string.default_browser_experiment_card_title),
                 onClick = {},
                 onCloseButtonClick = {},
             )
@@ -245,7 +245,7 @@ private fun MessageCardWithButtonLabelPreview() {
         ) {
             MessageCard(
                 messageText = stringResource(id = R.string.default_browser_experiment_card_text),
-                titleText = stringResource(id = R.string.bookmark_empty_title_error),
+                titleText = stringResource(id = R.string.default_browser_experiment_card_title),
                 buttonText = stringResource(id = R.string.preferences_set_as_default_browser),
                 onClick = {},
                 onCloseButtonClick = {},

app/src/main/res/values/strings.xml

@@ -2089,6 +2089,9 @@
     <string name="other_default_search_engine_suggestion_header">%s search</string>
 
     <!-- Default browser experiment -->
+    <!-- Default browser card title -->
+    <string name="default_browser_experiment_card_title">Switch your default browser</string>
+    <!-- Default browser card text -->
     <string name="default_browser_experiment_card_text">Set links from websites, emails, and messages to open automatically in Firefox.</string>
 
     <!-- Content description for close button in collection placeholder. -->