Remove unused variable SKIP_BOOT_JARS_CHECK.

The variable is no longer used after https://r.android.com/1737753.

Bug: 189298093
Test: m
Change-Id: I7f660fb205212d109f3e9ce2c805508ef481da24

android/config.go

@@ -854,11 +854,6 @@ func (c *config) AlwaysUsePrebuiltSdks() bool {
 	return Bool(c.productVariables.Always_use_prebuilt_sdks)
 }
 
-// Returns true if the boot jars check should be skipped.
-func (c *config) SkipBootJarsCheck() bool {
-	return Bool(c.productVariables.Skip_boot_jars_check)
-}
-
 func (c *config) MinimizeJavaDebugInfo() bool {
 	return Bool(c.productVariables.MinimizeJavaDebugInfo) && !Bool(c.productVariables.Eng)
 }