[SwiftPM] Pass --reconfigure when building swiftpm

This should help in avoiding incremental build issues on the CI

<rdar://problem/58287933> PR test failure to build swiftpm

Author: aciidgh

utils/swift_build_support/swift_build_support/products/swiftpm.py

@@ -58,7 +58,7 @@ def run_bootstrap_script(self, action, host_target, additional_params=[]):
         shell.call(helper_cmd)
 
     def build(self, host_target):
-        self.run_bootstrap_script('build', host_target)
+        self.run_bootstrap_script('build', host_target, ["--reconfigure"])
 
     def should_test(self, host_target):
         return self.args.test_swiftpm