test(packages): Add non-regression test for urlstyle

tests/feat-urlstyle.expected

@@ -0,0 +1,52 @@
+Set paper size 	297.6377985	419.5275636
+Begin page
+Mx 	14.8819
+My 	26.2947
+Set font 	Hack;7;400;;normal;;;LTR
+T	156 211 211 198 205 w=21.0718	(https)
+Mx 	35.9537
+T	583 w=4.2144	(:)
+Mx 	40.1680
+T	599 w=4.2144	(/)
+Mx 	44.3824
+T	599 w=4.2144	(/)
+Mx 	48.5967
+T	205 158 172 139 w=16.8574	(sile)
+Mx 	65.4542
+T	656 w=4.2144	(-)
+Mx 	69.6685
+T	211 233 198 139 205 139 211 211 139 201 w=42.1436	(typesetter)
+Mx 	111.8121
+T	592 w=4.2144	(.)
+Mx 	116.0264
+T	184 201 151 w=12.6431	(org)
+Mx 	128.6695
+T	599 w=4.2144	(/)
+Mx 	14.8819
+My 	38.2947
+Set font 	Gentium Plus;10;400;;normal;;;LTR
+T	31 w=4.3896	(<)
+Mx 	19.2715
+T	75 87 87 83 86 w=21.5625	(https)
+Mx 	40.8340
+T	29 w=2.2900	(:)
+Mx 	43.1241
+T	18 w=4.6924	(/)
+Mx 	47.8165
+T	18 w=4.6924	(/)
+Mx 	52.5088
+T	86 76 79 72 w=13.9014	(sile)
+Mx 	66.4102
+T	16 w=3.3691	(-)
+Mx 	69.7794
+T	87 92 83 72 86 72 87 87 72 85 w=42.2363	(typesetter)
+Mx 	112.0157
+T	17 w=2.2900	(.)
+Mx 	114.3057
+T	82 85 74 w=13.8672	(org)
+Mx 	128.1729
+T	18 w=4.6924	(/)
+Mx 	132.8653
+T	33 w=4.3896	(>)
+End page
+Finish

tests/feat-urlstyle.sil

@@ -0,0 +1,11 @@
+\begin[papersize=a6]{document}
+\neverindent
+\nofolios
+\use[module=packages.url]
+
+\url{https://sile-typesetter.org/}
+
+\define[command=urlstyle]{<{\process}>}
+\url{https://sile-typesetter.org/}
+
+\end{document}