[SWIG] fix compiler warning about unused variable in SWIG

[StrikerRUS]

D:\a\1\s\build\java\lightgbmlibJAVA_wrap.cxx(792): warning C4101: 'e': unreferenced local variable [D:\a\1\s\build\_lightgbm_swig.vcxproj]
D:\a\1\s\build\java\lightgbmlibJAVA_wrap.cxx(887): warning C4101: 'e': unreferenced local variable [D:\a\1\s\build\_lightgbm_swig.vcxproj]
D:\a\1\s\build\java\lightgbmlibJAVA_wrap.cxx(925): warning C4101: 'e': unreferenced local variable [D:\a\1\s\build\_lightgbm_swig.vcxproj]
D:\a\1\s\build\java\lightgbmlibJAVA_wrap.cxx(964): warning C4101: 'e': unreferenced local variable [D:\a\1\s\build\_lightgbm_swig.vcxproj]

[github-actions]

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