For easier debugging, if the PDB is not deployed, add the Method Token and IL Offset to the stacktrace.
This functionality can be turned on and off by environment setting "COMPlus_ILOffsetToStackTrace"

Use LocalAppContextSwitch to get environment variable without using static constructor in StackTrace.
Also, use HexConverter to get metadata token and il offset without unnecessary complex.

Use AppendFormat() for formatting of the hex number.

- Change switch name from ILOffsetsToStackTrace to ShowILOffset
- Use "Switch.System.Diagnostics.StackTrace.ShowILOffsets" to activate ILOffset in stacktrace
- Use "DOTNET_" prefix for environment variable name (DOTNET_ILOffsetToStackTrace)

…tSwitches.cs

Co-authored-by: Noah Falk <noahfalk@users.noreply.github.com>

remove setting code using environment variable and change switch default value to true.

Related issue : dotnet#51096