Fix strips text offset when zooming VSE timeline

Glyph cache is cleared by UI_view2d_zoom_cache_reset, when zooming V2D, but is required to calculate text height in UI_view2d_text_cache_draw

This caused text in strips to "jump around"

There was a comment in UI_view2d_zoom_cache_reset:
While scaling we can accumulate fonts at many sizes (~20 or so).
Not an issue with embedded font, but can use over 500Mb with i18n ones! See [#38244].

source/blender/editors/interface/view2d.c

@@ -2572,6 +2572,8 @@ void UI_view2d_text_cache_draw(ARegion *ar)
 
 	/* investigate using BLF_ascender() */
 	const int font_id = BLF_default();
+
+	BLF_set_default();
 	const float default_height = g_v2d_strings ? BLF_height(font_id, "28", 3) : 0.0f;
 
 	wmOrtho2_region_pixelspace(ar);