Fix issue11359 primitiveStringReplace by applying Newspeak fix

This enables this snippet to work, not a major fix, but nice to have:
| array1 array2 |
array1 := (1 to: 10) asArray.
array1 replaceFrom: 5 to: 10 with: array1 startingAt: 2.
array2 := (1 to: 10) asArray.
array2 replaceFrom: 5 to: 10 with: array2 copy startingAt: 2.
self assert: array1 = array2
See https://pharo.fogbugz.com/f/cases/11359/Use-memmove-instead-of-memcpy-in-primitives