[yul-phaser] Move stripWhitespace() from Program tests to Common

test/yulPhaser/Common.cpp

@@ -19,6 +19,8 @@
 
 #include <libyul/optimiser/Suite.h>
 
+#include <regex>
+
 using namespace std;
 using namespace solidity;
 using namespace solidity::yul;
@@ -32,3 +34,9 @@ map<string, size_t> phaser::test::enumerateOptmisationSteps()
 
 	return stepIndices;
 }
+
+string phaser::test::stripWhitespace(string const& input)
+{
+	regex whitespaceRegex("\\s+");
+	return regex_replace(input, whitespaceRegex, "");
+}