A dot has a special meaning in regexes, it matches any character except newline. To match a literal dot, you need to backslash it.

Moreover, you probably don't want to remove a dot from somewhere further inside the string, only the starting one. You can add ^ to the regex, it only matches at the beginning of the string.

The final g means "global", it will remove all the occurrences of the pattern. As we only want to remove a single occurrence, we don't need it.

$file =~ s{^\.}{};
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