[fenix] For https://github.com/mozilla-mobile/fenix/issues/23191 - Replace @color/preference_section_header_normal_theme with @color/fx_mobile_text_color_accent

app/src/main/res/values-night/colors.xml

@@ -135,7 +135,6 @@
     <color name="search_suggestion_indicator_icon_bookmark_color_normal_theme">@color/photonBlue40</color>
     <color name="select_login_header_normal_theme">@color/accent_high_contrast_dark_theme</color>
     <color name="select_credit_card_header_normal_theme">@color/accent_high_contrast_dark_theme</color>
-    <color name="preference_section_header_normal_theme">@color/accent_high_contrast_dark_theme</color>
     <color name="notification_accent_color_normal_theme">@color/accent_high_contrast_dark_theme</color>
     <color name="menu_item_button_normal_theme">@color/accent_high_contrast_dark_theme</color>
     <color name="recently_used_share_theme">@color/photonDarkGrey10</color>

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

@@ -141,7 +141,6 @@
     <color name="accent_bright_light_theme">@color/photonViolet70</color>
     <color name="dark_grey_90_gradient_start">@color/photonDarkGrey90</color>
     <color name="dark_grey_90_gradient_end">#0015141A</color>
-    <color name="preference_section_header_normal_theme">@color/accent_bright_light_theme</color>
 
     <!-- Dark theme color palette -->
     <color name="accent_bright_dark_theme">@color/photonViolet70</color>

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

@@ -82,7 +82,7 @@
         <item name="awesomeBarIndicatorBookmarkColor">@color/search_suggestion_indicator_icon_bookmark_color_normal_theme</item>
         <item name="selectLoginHeaderTextColor">@color/select_login_header_normal_theme</item>
         <item name="selectCreditCardHeaderTextColor">@color/select_credit_card_header_normal_theme</item>
-        <item name="preferenceSectionHeader">@color/preference_section_header_normal_theme</item>
+        <item name="preferenceSectionHeader">@color/fx_mobile_text_color_accent</item>
         <item name="menuItemButtonTintColor">@color/menu_item_button_normal_theme</item>
         <item name="recentlyUsedShareMenu">@color/recently_used_share_theme</item>