Possible lastUpdateCheck timestamp file corruption in UpdateChecker

[chanseokoh]

This looks like a very similar (or the same) problem to #2294. However, this is a fairly minor and low-priority problem and mostly benign, because we auto-generate and overwrite the file every time. It will just be that Jib may do more frequent, unintended update checks.

In #2335, I saw this log:

03:03:20.913 [DEBUG] [org.gradle.api.Task] Failed to read lastUpdateCheck; Text '' could not be parsed at index 0

I am only guessing, but the message sounds like the file was empty.

We overwrite the file with Files.write(), and the JDK code works by opening an OutputStream. So I think it can have the same truncating issue with #2294.

        try (OutputStream out = Files.newOutputStream(path, options)) {
                ...
                out.write(bytes, (len-rem), n);

[chanseokoh]

It will just be that Jib may do more frequent, unintended update checks.

I think it's better to fix this earlier than later, because the metrics may get skewed when we fix this eventually.