预览报表时，占用的内存在取消预览后，内存不释放

[liph7268]

版本号：

1.9.1

问题描述：

在报表的每一个列字段中都写有表达式（大约有10列），当数据较多时，打开预览后，占用后端内存较多，当结束预览时，且内存不会自动释放，导致程序占用内存越来越多，最终出现服务器卡死、崩溃的现象

错误截图：

http://ram.sdjcf.com/api/customerReport/detail?id=55&flg=0

http://ram.sdjcf.com:9190/jmreport/getQueryInfo?reportId=732375391416348672&param=%7B%22htnm%22:%22215%22,%22qsrq%22:%222024-10-18%22,%22zzrq%22:%222024-12-17%22,%22cknm%22:%22%22,%22jsfs%22:%22%E7%AE%97%E5%A4%B4%E5%8F%88%E7%AE%97%E5%B0%BE%22,%22dkzj_flg%22:%220%22,%22mini_jsrs%22:%220%22,%22zje%22:%221228890.84%22,%22dsje%22:%220%22,%22htbzj_flg%22:%220%22,%22jsrqfs%22:%221%22,%22pmzjnms%22:%22%22,%22pmxlflg%22:%220%22,%22token%22:%22eyJhbGciOiJIUzUxMiJ9.eyJsb2dpbl91c2VyX2tleSI6InBjJiYmNmY1ZWE4YWUtZGU3Ni00YWQwLTg1NTktMjY5OWZiZGU1ZjBhIyMjIyMjc2R6Zl96bGdsX2NoZW45OTYxNGE2MmQwMWU1In0.ylWop_EyLSmx3uEkxSJ-P7Kpd-JrgQDfFDrGPaFtLGfZjwQoj48J72zsWASueAdn6HJGIdXFqa0IXROAl_ch4g%22%7D

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