vim-patch:9.1.0655: filetype: goaccess config file not recognized

Problem:  filetype: goaccess config file not recognized
Solution: detect 'goaccess.conf' as goaccess filetype, also
          include a basic syntax and ftplugin (Adam Monsen)

Add syntax highlighting for GoAccess configuration file.

GoAccess is a real-time web log analyzer and interactive viewer that
runs in a terminal in *nix systems or through your browser.

GoAccess home page: https://goaccess.io

closes: vim/vim#15414

0aa65b48fb

Co-authored-by: Adam Monsen <haircut@gmail.com>

test/old/testdir/test_filetype.vim

@@ -301,6 +301,7 @@ func s:GetFilenameChecks() abort
     \ 'gnash': ['gnashrc', '.gnashrc', 'gnashpluginrc', '.gnashpluginrc'],
     \ 'gnuplot': ['file.gpi', '.gnuplot', 'file.gnuplot', '.gnuplot_history'],
     \ 'go': ['file.go'],
+    \ 'goaccess': ['goaccess.conf'],
     \ 'gomod': ['go.mod'],
     \ 'gosum': ['go.sum', 'go.work.sum'],
     \ 'gowork': ['go.work'],