Update to Stubparser 3.26.4 (#7058)

Author: smillst

framework/build.gradle

@@ -33,8 +33,8 @@ configurations {
 dependencies {
   api project(':javacutil')
   api project(':dataflow')
-  api 'org.checkerframework:stubparser:3.26.2'
-  stubifierImplementation 'org.checkerframework:stubparser:3.26.2'
+  api 'org.checkerframework:stubparser:3.26.4'
+  stubifierImplementation 'org.checkerframework:stubparser:3.26.4'
   implementation sourceSets.stubifier.output
   // AFU is an "includedBuild" imported in checker-framework/settings.gradle, so the version number doesn't matter.
   // https://docs.gradle.org/current/userguide/composite_builds.html#settings_defined_composite