use fixed-size buffer in RedirectablePrint::vprintf() (#1622)

Co-authored-by: Peter Lawrence <12226419+majbthrd@users.noreply.github.com>
Co-authored-by: Garth Vander Houwen <garthvh@yahoo.com>
Co-authored-by: Ben Meadors <benmmeadors@gmail.com>

src/RedirectablePrint.h

@@ -12,10 +12,6 @@ class RedirectablePrint : public Print
 {
     Print *dest;
 
-    /// We dynamically grow this scratch buffer if necessary
-    char *printBuf = new char[64];
-    size_t printBufLen = 64;
-
     /// Used to allow multiple logDebug messages to appear on a single log line
     bool isContinuationMessage = false;