Remove extra at sign

Author: samanklesaria

docs/Makefile

@@ -25,7 +25,7 @@ docset: html
 # "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
 %: Makefile
 	doxygen source/Doxyfile
-	PYTHONPATH="$(realpath ../test)" @$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+	PYTHONPATH="$(realpath ../test)" $(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
 	@python post_process_dispatcher.py $(BUILDDIR)
 
 clean: