message: fix for when tex file is not in workspace root
diff: @@ -114,7 +114,8 @@ async function onClientMessage(msg) {
  let row = record["line"] - 1;
  let pos = new vscode.Position(row, col);
  - let doc = await vscode.workspace.openTextDocument(record["input"].replace(/(\r\n|\n|\r)/gm,""));
  + let file = path.join(path.dirname(latex_data.main_document), record["input"].replace(/(\r\n|\n|\r)/gm,""));
  + let doc = await vscode.workspace.openTextDocument(file);
  let editor = await vscode.window.showTextDocument(doc);
  editor.selection = new vscode.Selection(pos, pos);
  await vscode.commands.executeCommand("revealLine", {lineNumber: row, at: 'center'});
  