fix(gomod): support major version on replaces with the same Go module

[jamietanna]

Changes

As noted in #41260, if a Go module is using a replace with both
modules with the same name, the major upgrade fails to produce a valid
go.mod, as the replace will still partially reference the old
package.

Context

Please select one of the below:

• This closes an existing Issue: Closes #
• This doesn't close an Issue, but I accept the risk that this PR may be closed if maintainers disagree with its opening or implementation

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The public repository: JamieTanna-Mend-testing/renovate-iss-41260-gomod-bug-test#1