add null check in SubProcessTaskExecThread (#1737)

* modify FileUtils.readFile2Str

* #1300 Add right alignment function in sql email content

* cancel formatted for alert_mail_template.ftl

* #747 sql task password Log desensitization

* cancel mail_temple

* edit ExcelUtils

* modify test method name

* #747 sql task password Log desensitization

* #1544 workflow import

* Constants add DATASOURCE_PASSWORD_REGEX

* #747 sql task password Log desensitization

* deal with import project have sub process

* modify export process addTaskNodeParam method name

* add testAddTaskNodeSpecialParam UT

* add ProcessDefinitionServiceTest-ut to pom

* add testImportSubProcess in ProcessDefinitionServiceTest

* add testImportSubProcess in ProcessDefinitionServiceTest

* add testImportProcessDefinition

* fix sonar bug: not enough arguments

* fix sonar bug: change condition & not enough arguments

* fix bug sonar: add null check in daghelper && add hashcode method in ProcessData

* fix bug sonar: add null check in daghelper

* CollectionUtils.isEmpty()

* add hashcode() && null check

* merge if

* remove hashcode

* remove e.getMessage