Integrated: Remove spurious `^` char from tarball name

[Athijegannathan Sundararajan]

On Tue, 19 Jul 2022 10:36:34 GMT, Maurizio Cimadamore <mcimadamore at openjdk.org> wrote:

> As the title says, this simple patch removes a spurious `^` char in the replacement text of a substitution applied during the tarball generation.
> Because of that, on Linux, the generated tarball has a topdir named `^jextract-<version>`.

LGTM

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Marked as reviewed by sundar (Committer).

PR: https://git.openjdk.org/jextract/pull/54