Draft: Upgrade go-paths-helper to patched version

This commit should not be merged, instead the indicated commit should be
merged into upstream go-paths-helper first and this commit adapted.

This makes two relevant changes:
 - ReadDirRecursive now returns broken symlinks as-is (and other files
   that cannot be stat'd due to permission errors) rather than failing
   entirely. This causes broken symlinks to no longer break the build,
   unless they are actually used (i.e. broken .cpp links will cause gcc
   to error out later).
 - FilterOutDirs no longer filters out broken symlinks (and other files
   that cannot be stat'd due to whatever error). This ensures that
   broken symlinks are actually returned by Sketch.supportedFiles, so
   sketch.New can check them (though that still ignores any errors
   currently).

The test suite is updated for these changes.

Author: matthijskooijman

go.mod

@@ -52,3 +52,5 @@ require (
 	gopkg.in/src-d/go-git.v4 v4.13.1
 	gopkg.in/yaml.v2 v2.4.0
 )
+
+replace github.com/arduino/go-paths-helper v1.6.1 => github.com/matthijskooijman/go-paths-helper v1.6.2-0.20210908151509-429170ecd10a

test/test_compile.py

@@ -220,11 +220,11 @@ def test_broken_symlink(sketch_name, link_name, target_name, expect_error):
         else:
             assert result.ok
 
-    test_broken_symlink("CompileIntegrationTestSymlinkBrokenIno", "link.ino", "doesnotexist.ino", expect_error=True)
-    test_broken_symlink("CompileIntegrationTestSymlinkBrokenCpp", "link.cpp", "doesnotexist.cpp", expect_error=True)
-    test_broken_symlink("CompileIntegrationTestSymlinkBrokenH", "link.h", "doesnotexist.h", expect_error=True)
-    test_broken_symlink("CompileIntegrationTestSymlinkBrokenJson", "link.json", "doesnotexist.json", expect_error=True)
-    test_broken_symlink("CompileIntegrationTestSymlinkBrokenXXX", "link.xxx", "doesnotexist.xxx", expect_error=True)
+    test_broken_symlink("CompileIntegrationTestSymlinkBrokenIno", "link.ino", "doesnotexist.ino", expect_error=False)
+    test_broken_symlink("CompileIntegrationTestSymlinkBrokenCpp", "link.cpp", "doesnotexist.cpp", expect_error=False)
+    test_broken_symlink("CompileIntegrationTestSymlinkBrokenH", "link.h", "doesnotexist.h", expect_error=False)
+    test_broken_symlink("CompileIntegrationTestSymlinkBrokenJson", "link.json", "doesnotexist.json", expect_error=False)
+    test_broken_symlink("CompileIntegrationTestSymlinkBrokenXXX", "link.xxx", "doesnotexist.xxx", expect_error=False)
 
 
 def test_compile_blacklisted_sketchname(run_command, data_dir):