[internal] Include link dest in symlink error. (#14384)
[internal] Include link dest in symlink error. (#14384)

I think it is relevant to include the rejected target path (`path_buf`) in the error message, and the `link_abs` is already presented in the outer error message `"Failed to read link <link_abs>: ..."` which was giving us the same path info twice.

Example:
```
Failed to read link "/private/tmp/process-executionCEiV14/.docker_tools/sh": Absolute symlink: "/private/tmp/process-executionCEiV14/.docker_tools/sh"
```
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