docs: changelog for #891

docs/changelog.md

@@ -45,6 +45,7 @@ As features stabilize some brief notes about them will accumulate here.
 * Fixed: closing last pane in a tab via `CloseCurrentPane` could cause the window to close [#890](https://github.com/wez/wezterm/issues/890)
 * Improved: `wezterm ls-fonts --list-system` shows all available fonts, `wezterm ls-fonts --text "hello"` explains which fonts are used for each glyph in the supplied text
 * Fixed: mouse cursor is now Arrow rather than I-beam when the application in the terminal has enabled mouse reporting [#859](https://github.com/wez/wezterm/issues/859)
+* Improved: DEC Special Graphics mode conformance and complete coverage of the graphics character set. Thanks to [Autumn Lamonte](https://gitlab.com/klamonte)! [#891](https://github.com/wez/wezterm/pull/891)
 
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