bmpblk: Prevent symbols from inflating text bitmap height

Add pango markup around symbols that prevents changing text bitmap
height. Pango uses different font (Noto Sans Symbols) to print symbols.
That font has greater height to accommodate vertical symbols. However
symbols used by us don't take more vertical space than regular font. Use
"line_height" modifier to ignore height required by the symbols font.

BUG=b:488289370
BRANCH=main
TEST=Verified that all screens are displayed correctly

Change-Id: I833ff3d98a0bf0e541903b574f29f962cf4af2e2
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/bmpblk/+/7737701
Reviewed-by: Yu-Ping Wu <yupingso@chromium.org>
Tested-by: Tomasz Michalec <tmichalec@google.com>
Commit-Queue: Tomasz Michalec <tmichalec@google.com>
Reviewed-by: Julius Werner <jwerner@chromium.org>
GitOrigin-RevId: 7397809643da376f2b85555e660ab3583af494d2