UTF8 error installning brew

[Vainyards]

==> Installing astroidmail/astroid/astroid dependency: webkitgtk
==> Patching
==> cmake -GNinja -DPORT=GTK -DCMAKE_BUILD_TYPE=RelWithDebInfo -DENABLE_INTROSPECTION=OFF -DENABLE_GEOLOCATION=OFF -DENABLE_OPENGL=OFF -DENABLE_VIDEO=OFF -DENABLE_WEB_AUDIO
==> ninja install
Last 15 lines from /Users/mbp/Library/Logs/Homebrew/webkitgtk/02.ninja:
#include "unicode/utf8.h"
^~~~~~~~~~~~~~~~
"unicode/UTF8.h"
In file included from ../Source/WTF/wtf/text/WTFString.cpp:23:
In file included from ../Source/WTF/wtf/text/WTFString.h:32:
In file included from ../Source/WTF/wtf/text/StringImpl.h:27:
In file included from /usr/local/opt/icu4c/include/unicode/ustring.h:21:
In file included from /usr/local/opt/icu4c/include/unicode/utypes.h:44:
In file included from /usr/local/opt/icu4c/include/unicode/utf.h:221:
/usr/local/opt/icu4c/include/unicode/utf_old.h:146:10: warning: non-portable path to file '"unicode/UTF8.h"'; specified path differs in case from file name on disk [-Wnonportable-include-path]
#include "unicode/utf8.h"
^~~~~~~~~~~~~~~~
"unicode/UTF8.h"
2 warnings generated.
ninja: build stopped: subcommand failed.

If reporting this issue please do so at (not Homebrew/brew or Homebrew/core):
https://github.com/astroidmail/homebrew-astroid/issues

Just got a new macbook pro, tried to install on big-sur, but got the same as I did on my old Macbook air.

How can this be resolved?!