Relationships in case of cells with hyperlinks are duplicated on every workbook.save()

Try running the following code in OpenPyXL 3.0.3:

from openpyxl import load_workbook
wb = load_workbook("test_before.xlsx")
for a in range(100):
    wb.save("test_after.xlsx")

This results in sheet1.xml (I access it by opening test_after.xlsx using 7z or similar and navigating to xl/worksheets folder) containing

<hyperlinks>
<hyperlink ref="A1" r:id="rId100" />
<hyperlink ref="A1" r:id="rId100" />
<hyperlink ref="A1" r:id="rId100" />
<hyperlink ref="A1" r:id="rId100" />
<hyperlink ref="A1" r:id="rId100" />
<hyperlink ref="A1" r:id="rId100" />
<hyperlink ref="A1" r:id="rId100" />
<hyperlink ref="A1" r:id="rId100" />
<hyperlink ref="A1" r:id="rId100" />
<hyperlink ref="A1" r:id="rId100" />
...

and the _rels directory has sheet1.xml.rels with contents

<Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">
<Relationship Id="rId1" Target="http://example.com/" TargetMode="External" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/hyperlink" />
<Relationship Id="rId2" Target="http://example.com/" TargetMode="External" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/hyperlink" />
<Relationship Id="rId3" Target="http://example.com/" TargetMode="External" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/hyperlink" />
<Relationship Id="rId4" Target="http://example.com/" TargetMode="External" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/hyperlink" />
<Relationship Id="rId5" Target="http://example.com/" TargetMode="External" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/hyperlink" />
<Relationship Id="rId6" Target="http://example.com/" TargetMode="External" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/hyperlink" />
<Relationship Id="rId7" Target="http://example.com/" TargetMode="External" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/hyperlink" />
<Relationship Id="rId8" Target="http://example.com/" TargetMode="External" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/hyperlink" />
<Relationship Id="rId9" Target="http://example.com/" TargetMode="External" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/hyperlink" />
<Relationship Id="rId10" Target="http://example.com/" TargetMode="External" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/hyperlink" />
...

Clearly this is not the intended behavior, because for larger sheets with lots of links this gets out of control very fast. So, in my opinion, a pretty serious issue.

test_before.xlsx test_after.xlsx