Remove language warnings during Windows setup compilation

When compiling the Windows installer, you get the following warnings:

7025: "${LANG_ENGLISH}" is not a valid language id, using language id 1033! (E:\Externe projecten\GeoServer\src\release\installer\win\GeoServerEXE.nsi:69)
7025: "${LANG_ENGLISH}" is not a valid language id, using language id 1033! (E:\Externe projecten\GeoServer\src\release\installer\win\GeoServerEXE.nsi:70)
7025: "${LANG_ENGLISH}" is not a valid language id, using language id 1033! (E:\Externe projecten\GeoServer\src\release\installer\win\GeoServerEXE.nsi:71)
7025: "${LANG_ENGLISH}" is not a valid language id, using language id 1033! (E:\Externe projecten\GeoServer\src\release\installer\win\GeoServerEXE.nsi:72)
7025: "${LANG_ENGLISH}" is not a valid language id, using language id 1033! (E:\Externe projecten\GeoServer\src\release\installer\win\GeoServerEXE.nsi:73)
7025: "${LANG_ENGLISH}" is not a valid language id, using language id 1033! (E:\Externe projecten\GeoServer\src\release\installer\win\GeoServerEXE.nsi:74)
7025: "${LANG_ENGLISH}" is not a valid language id, using language id 1033! (E:\Externe projecten\GeoServer\src\release\installer\win\GeoServerEXE.nsi:75)
7025: "${LANG_ENGLISH}" is not a valid language id, using language id 1033! (E:\Externe projecten\GeoServer\src\release\installer\win\GeoServerEXE.nsi:76)
7025: "${LANG_ENGLISH}" is not a valid language id, using language id 1033! (E:\Externe projecten\GeoServer\src\release\installer\win\GeoServerEXE.nsi:77)
7025: "${LANG_ENGLISH}" is not a valid language id, using language id 1033! (E:\Externe projecten\GeoServer\src\release\installer\win\GeoServerEXE.nsi:78)
7025: "${LANG_ENGLISH}" is not a valid language id, using language id 1033! (E:\Externe projecten\GeoServer\src\release\installer\win\GeoServerEXE.nsi:79)
7025: "${LANG_ENGLISH}" is not a valid language id, using language id 1033! (E:\Externe projecten\GeoServer\src\release\installer\win\GeoServerEXE.nsi:80)