fix issue 11431 - std.file.slurp fails with Windows newlines

std/file.d

@@ -5098,13 +5098,15 @@ slurp(Types...)(string filename, scope const(char)[] format)
     import std.exception : enforce;
     import std.format : formattedRead;
     import std.stdio : File;
+    import std.string : stripRight;
 
     auto app = appender!(typeof(return))();
     ElementType!(typeof(return)) toAdd;
     auto f = File(filename);
     scope(exit) f.close();
     foreach (line; f.byLine())
     {
+        line = stripRight(line, "\r");
         formattedRead(line, format, &toAdd);
         enforce(line.empty,
                 text("Trailing characters at the end of line: `", line,
@@ -5135,6 +5137,19 @@ slurp(Types...)(string filename, scope const(char)[] format)
     assert(a[1] == tuple(345, 1.125));
 }
 
+@system unittest
+{
+    import std.typecons : tuple;
+
+    scope(exit)
+    {
+        assert(exists(deleteme));
+        remove(deleteme);
+    }
+    write(deleteme, "10\r\n20");
+    assert(slurp!(int)(deleteme, "%d") == [10, 20]);
+}
+
 
 /**
 Returns the path to a directory for temporary files.