add the build directory to gitignore

necto · necto · commit dac0e86c1ac1 · 2021-06-14T18:16:23.000+02:00
diff --git a/.gitignore b/.gitignore
@@ -9,3 +9,4 @@ install_manifest.txt
 compile_commands.json
 CTestTestfile.cmake
 _deps
+build/
