Update constant current diode as per IEC60747-3:2013

This MR updates the D_Constant_Current Symbol introduced in !4122 (merged).

@vincent-lorentz found the corresponding IEC Symbol in the IEC 60747-3:2013 and detailed the required changes over at !4122 (comment 1842141507).

This MR changes the following three things:

• The name of the symbol is changed from D_Constant_Current to D_Current-regulator
• A small arrow was added
• I have also added the term IEC60747-3:2013 to the description, so that this information will not be lost over time

I have added @vincent-lorentz as a co-author to this MR.

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