Disable historical_weather()

[jonocarroll]

Disables get_historical_weather() with a reference to the BOM site and the discussion page.

• Tests all contain skip_on_cran() anyway, and these still pass

withr::with_envvar(c(NOT_CRAN = "false"), devtools::test()) 
── Skipped tests  ─────────────────
● On CRAN (92)

[ FAIL 0 | WARN 0 | SKIP 92 | PASS 5 ]

• Changed example to wrapped in \dontrun{}

[maelle]

From the README

This package has been archived due to BOM's ongoing unwillingness to allow programmatic access to their data and actively blocking any attempts made using this package or other similar efforts.