escape SP to underscore

Author: smdn

src/Smdn.MSBuild.DefineConstants.NETSdkApi/build/Smdn.MSBuild.DefineConstants.NETSdkApi.targets

@@ -584,6 +584,7 @@ SPDX-License-Identifier: MIT
           .Replace('+', '_')
           .Replace(':', '_')
           .Replace('`', '_')
+          .Replace(' ', '_')
           .ToUpperInvariant()
         )</Constant>
       </_NETSdkAvailableApiSymbol>

tests/Smdn.MSBuild.DefineConstants.NETSdkApi/Test.NETSTANDARD2_1_OR_GREATER+NETCOREAPP2_0_OR_GREATER+NET5_0_OR_GREATER.cs

@@ -4,4 +4,8 @@
   #if !SYSTEM_ARRAYSEGMENT_SLICE
     #error "SYSTEM_ARRAYSEGMENT_SLICE is not defined"
   #endif
+
+  #if !SYSTEM_COLLECTIONS_GENERIC_DICTIONARY_REMOVE_TKEY_OUT_TVALUE
+    #error "SYSTEM_COLLECTIONS_GENERIC_DICTIONARY_REMOVE_TKEY_OUT_TVALUE is not defined"
+  #endif
 #endif