Deprecated usage of `isLoading` in react query

[corneliusroemer]

https://github.com/loculus-project/loculus/actions/runs/15719098157/job/44296100270?pr=4442#step:6:38

See: TanStack/query#9266

Noticed in: #4442

/home/runner/work/loculus/loculus/website/src/components/DataUseTerms/EditDataUseTermsModal.tsx
Error:   115:25  error  `isLoading` is deprecated. This property will be removed in the next major version. Use `isPending` instead  @typescript-eslint/no-deprecated
Error:   126:58  error  `isLoading` is deprecated. This property will be removed in the next major version. Use `isPending` instead  @typescript-eslint/no-deprecated

/home/runner/work/loculus/loculus/website/src/components/Edit/EditPage.tsx
Error:   45:37  error  `isLoading` is deprecated. This property will be removed in the next major version. Use `isPending` instead  @typescript-eslint/no-deprecated
Error:   53:33  error  `isLoading` is deprecated. This property will be removed in the next major version. Use `isPending` instead  @typescript-eslint/no-deprecated

/home/runner/work/loculus/loculus/website/src/components/SearchPage/SearchFullUI.tsx
Error:   412:47  error  `isLoading` is deprecated. This property will be removed in the next major version. Use `isPending` instead  @typescript-eslint/no-deprecated
Error:   412:75  error  `isLoading` is deprecated. This property will be removed in the next major version. Use `isPending` instead  @typescript-eslint/no-deprecated
Error:   426:42  error  `isLoading` is deprecated. This property will be removed in the next major version. Use `isPending` instead  @typescript-eslint/no-deprecated
Error:   427:44  error  `isLoading` is deprecated. This property will be removed in the next major version. Use `isPending` instead  @typescript-eslint/no-deprecated

/home/runner/work/loculus/loculus/website/src/components/SearchPage/fields/AutoCompleteOptions.ts
Error:    56:23  error  `isLoading` is deprecated. This property will be removed in the next major version. Use `isPending` instead  @typescript-eslint/no-deprecated
Error:   169:13  error  `isLoading` is deprecated. This property will be removed in the next major version. Use `isPending` instead  @typescript-eslint/no-deprecated

/home/runner/work/loculus/loculus/website/src/components/SeqSetCitations/SeqSetForm.tsx
Error:   279:27  error  `isLoading` is deprecated. This property will be removed in the next major version. Use `isPending` instead  @typescript-eslint/no-deprecated
Error:   279:47  error  `isLoading` is deprecated. This property will be removed in the next major version. Use `isPending` instead  @typescript-eslint/no-deprecated

/home/runner/work/loculus/loculus/website/src/components/Submission/DataUploadForm.tsx
Error:   449:27  error  `isLoading` is deprecated. This property will be removed in the next major version. Use `isPending` instead  @typescript-eslint/no-deprecated
Error:   449:47  error  `isLoading` is deprecated. This property will be removed in the next major version. Use `isPending` instead  @typescript-eslint/no-deprecated

✖ [14](https://github.com/loculus-project/loculus/actions/runs/15719098157/job/44296100270?pr=4442#step:6:15) problems (14 errors, 0 warnings)

Error: Process completed with exit code 1.