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](/uploads/f57ba00410c1d8ead69d814362a95837/test_before.xlsx)
[test_after.xlsx](/uploads/6fa3d459475f53b1232ba13b7dc0fabf/test_after.xlsx)
issue