Remove resolved issue with GCC/C++17

Author: tcsullivan

README.md

@@ -5,7 +5,6 @@
 * Convert any integral type to a string at compile-time
 * Supports converting to any base between 2 and 36 inclusive
 * No external dependencies, only includes `type_traits` for template parameter checking
-* Works best in C++20 GCC or C++17/20 Clang
 
 **How to use:**
 
@@ -22,10 +21,6 @@ With `to_string`, all that will be found in program disassembly are the resultin
 
 Try it [on Compiler Explorer](https://godbolt.org/z/T-MFoh).
 
-**Known issues:**
-
-* With C++17 GCC, `to_string` must be used to initialize variables; otherwise, the integer-string conversion is done at run-time.
-
 # How it works
 
 The basic structure of `to_string` is shown below: