`parse_timeset_input` should allow `"*"`

[brookslogan]

So we can take advantage of time_values="*" and issues="*" options again.

[brookslogan]

Reprex with user-facing function:

library(epidatr)
ga_hhs_issue_data =
  covidcast(
    "hhs", "confirmed_admissions_influenza_1d",
    geo_type = "state", time_type = "day",
    geo_values = "ga", time_values = "*",
    issues = "*"
  ) %>%
  fetch_tbl()
#> Error in parse_timeset_input(time_values): Invalid timeset input: *

^{Created on 2023-05-09 with reprex v2.0.2}