ROB: font_metrics: Add font aliases

Version 1.7 of the PDF reference lists various alternatives
names as accepted for the 14 core fonts, such as Arial for
Helvetica and CourierNew for Courier. Add these alternative
names to the font metrics.

Author: PJBrs

pypdf/_codecs/core_fontmetrics.py

@@ -4425,3 +4425,17 @@
     ),
 }
 
+
+# Add aliases per table H.3 on pp. 1109-1110 of the PDF 1.7 reference
+FONT_METRICS["Arial"] = FONT_METRICS["Helvetica"]
+FONT_METRICS["Arial,Italic"] = FONT_METRICS["Helvetica-Oblique"]
+FONT_METRICS["Arial,Bold"] = FONT_METRICS["Helvetica-Bold"]
+FONT_METRICS["Arial,BoldItalic"] = FONT_METRICS["Helvetica-BoldOblique"]
+FONT_METRICS["CourierNew"] = FONT_METRICS["Courier"]
+FONT_METRICS["CourierNew,Italic"] = FONT_METRICS["Courier-Oblique"]
+FONT_METRICS["CourierNew,Bold"] = FONT_METRICS["Courier-Bold"]
+FONT_METRICS["CourierNew,BoldItalic"] = FONT_METRICS["Courier-BoldOblique"]
+FONT_METRICS["TimesNewRoman"] = FONT_METRICS["Times-Roman"]
+FONT_METRICS["TimesNewRoman,Italic"] = FONT_METRICS["Times-Italic"]
+FONT_METRICS["TimesNewRoman,Bold"] = FONT_METRICS["Times-Bold"]
+FONT_METRICS["TimesNewRoman,BoldItalic"] = FONT_METRICS["Times-BoldItalic"]