Merge bitcoin-core/secp256k1#1227: readme: Use correct build type in …

…CMake/Windows build instructions

756b61d readme: Use correct build type in CMake/Windows build instructions (Tim Ruffing)

Pull request description:

ACKs for top commit:
  hebasto:
    ACK 756b61d, it is correct to provide the "RelWithDebInfo" configuration in multi-config setup, as the same build type is the default in single-config setups.

Tree-SHA512: e98a1519fdae4a29c7e06ecd0e68083acaf0f4fc14dfcd12282b89468052bb7c6c2fc7517c8526c9f7555a822a64b2f7c3f1ecc70d17e37a11d831d213f1daef

README.md

@@ -106,7 +106,7 @@ The following example assumes using of Visual Studio 2022 and CMake v3.21+.
 In "Developer Command Prompt for VS 2022":
 
     >cmake -G "Visual Studio 17 2022" -A x64 -S . -B build
-    >cmake --build build --config Release
+    >cmake --build build --config RelWithDebInfo
 
 Usage examples
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