feat(syntax): allow comments in pgfcoordinates

refer: #3159

Author: lervag

autoload/vimtex/syntax/p/pgfplots.vim

@@ -41,7 +41,9 @@ function! vimtex#syntax#p#pgfplots#load(cfg) abort " {{{1
 
 
   syntax match texPgfType "coordinates" contained nextgroup=texPgfCoordinates skipwhite skipnl
-  call vimtex#syntax#core#new_arg('texPgfCoordinates', {'contains': ''})
+  call vimtex#syntax#core#new_arg('texPgfCoordinates', {
+        \ 'contains': 'texComment'
+        \})
 
 
   syntax match texPgfNode "node" contained nextgroup=texTikzNodeOpt skipwhite skipnl

test/test-syntax/test-tikz.tex

@@ -94,4 +94,15 @@
   \label{fig:instspill-t}
 \end{figure}
 
+\begin{tikzpicture}
+  % a comment with correct highlighting
+  \begin{axis}
+    \addplot coordinates {
+        % a comment with incorrect highlighting
+        (0,0)
+        (1,1)
+      };
+  \end{axis}
+\end{tikzpicture}
+
 \end{document}