message: other: update built-in themes list in config
  Adds nord and nord-light as part of the description in the pre-defined config file.
diff: @@ -479,7 +479,7 @@ pub const OLD_CONFIG_TEXT: &str = r##"# This is a default config file for bottom
  #hide_table_gap = false
  # Disable mouse clicks
  #disable_click = false
  -# Built-in themes. Valid values are "default", "default-light", "gruvbox", "gruvbox-light"
  +# Built-in themes. Valid values are "default", "default-light", "gruvbox", "gruvbox-light", "nord", "nord-light"
  #color = "default"
  # Show memory values in the processes widget as values by default
  #mem_as_value = false
  