Fix citation

Double "Kindly cite the 'pxweb' R package as follows:"

pxweb_cite(px_data)
Statistics Sweden (2026). “Population by region, marital status, age, sex
and year.” [Data accessed 2026-09-01 14:21:01.450732 using pxweb R
package 1.0.0],
https://statistikdatabasen.scb.se/api/v2/tables/TAB638/data.

A BibTeX entry for LaTeX users is

@Misc{,
title = {Population by region, marital status, age, sex and year},
author = {{Statistics Sweden}},
organization = {Statistics Sweden},
year = {2026},
url = {https://statistikdatabasen.scb.se/api/v2/tables/TAB638/data},
note = {[Data accessed 2026-09-01 14:21:01.450732 using pxweb R package 1.0.0]},
}
Kindly cite the pxweb R package as follows:

Kindly cite the 'pxweb' R package as follows:

Magnusson M, Kainu M, Huovari J, Lahti L (2026). pxweb: R Interface to
PXWEB APIs. doi:10.32614/CRAN.package.pxweb
https://doi.org/10.32614/CRAN.package.pxweb, R package version 1.0.0,
https://github.com/rOpenGov/pxweb.

A BibTeX entry for LaTeX users is

@Manual{R-pxweb,
title = {{pxweb: R Interface to PXWEB APIs}},
doi = {10.32614/CRAN.package.pxweb},
author = {Mans Magnusson and Markus Kainu and Janne Huovari and Leo Lahti},
year = {2026},
version = {1.0.0},
note = {R package version 1.0.0},
url = {https://github.com/rOpenGov/pxweb},
}

Start by running pxweb_cite(px_data) and inspect the citation-generation entry point. Compare the result with the issue’s output: the duplicate “Kindly cite...” text should be removed while the data and package citations remain correctly presented.