Drop ineffective MATPLOTLIB_BACKEND export from test recipes

has2k1 · has2k1 · commit 429a37a70e93 · 2026-04-30T18:39:21.000+03:00
Each recipe line runs in its own subshell, so `export
MATPLOTLIB_BACKEND=agg` on one line never reached the `pytest` invocation
on the next line. The export was a no-op; remove it.
diff --git a/Makefile b/Makefile
@@ -74,15 +74,12 @@ typecheck:
 	$(UVRUN) pyright
 
 test0: clean-test
-	export MATPLOTLIB_BACKEND=agg
 	$(UVRUN) pytest
 
 test: clean-test
-	export MATPLOTLIB_BACKEND=agg
 	$(UVRUN) pytest -n auto
 
 test1: clean-test
-	export MATPLOTLIB_BACKEND=agg
 	$(UVRUN) pytest -n auto -p no:sugar
 
 visualize-tests:
