GH-33631: [R] Rewrite Jira ticket numbers in pkgdown documents to GitHub issue numbers (#34260)

Rewrite the Jira issue numbers to the GitHub issue numbers, so that the GitHub issue numbers are automatically linked to the issues by pkgdown's auto-linking feature.

Issue numbers have been rewritten based on the following correspondence.
Also, the pkgdown settings have been changed and updated to link to GitHub.

I generated the Changelog page using the `pkgdown::build_news()` function and verified that the links work correctly.

---
ARROW-6338	#5198
ARROW-6364	#5201
ARROW-6323	#5169
ARROW-6278	#5141
ARROW-6360	#5329
ARROW-6533	#5450
ARROW-6348	#5223
ARROW-6337	#5399
ARROW-10850	#9128
ARROW-10624	#9092
ARROW-10386	#8549
ARROW-6994	#23308
ARROW-12774	#10320
ARROW-12670	#10287
ARROW-16828	#13484
ARROW-14989	#13482
ARROW-16977	#13514
ARROW-13404	#10999
ARROW-16887	#13601
ARROW-15906	#13206
ARROW-15280	#13171
ARROW-16144	#13183
ARROW-16511	#13105
ARROW-16085	#13088
ARROW-16715	#13555
ARROW-16268	#13550
ARROW-16700	#13518
ARROW-16807	#13583
ARROW-16871	#13517
ARROW-16415	#13190
ARROW-14821	#12154
ARROW-16439	#13174
ARROW-16394	#13118
ARROW-16516	#13163
ARROW-16395	#13627
ARROW-14848	#12589
ARROW-16407	#13196
ARROW-16653	#13506
ARROW-14575	#13160
ARROW-15271	#13170
ARROW-16703	#13650
ARROW-16444	#13397
ARROW-15016	#13541
ARROW-16776	#13563
ARROW-15622	#13090
ARROW-18131	#14484
ARROW-18305	#14581
ARROW-18285	#14615
* Closes: #33631

Authored-by: SHIMA Tatsuya <ts1s1andn@gmail.com>
Signed-off-by: Sutou Kouhei <kou@clear-code.com>

Author: eitsupi