Bump R dependency to 4.5.0 (due to boom) and update test matrix

Author: kaybrodersen

.github/workflows/R-CMD-check.yaml

@@ -21,7 +21,6 @@ jobs:
           - {os: macOS-latest,   r: 'release'}
           - {os: windows-latest, r: 'release'}
           - {os: ubuntu-latest,   r: 'release'}
-          - {os: ubuntu-latest,   r: 'oldrel-1'}
 
     env:
       GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}

DESCRIPTION

@@ -20,7 +20,7 @@ Version: 1.4.1
 VignetteBuilder: knitr
 License: Apache License 2.0 | file LICENSE
 Imports: assertthat (>= 0.2.0), Boom, ggplot2, zoo
-Depends: bsts (>= 0.9.0)
+Depends: R (>= 4.5.0), bsts (>= 0.9.0)
 Config/testthat/edition: 3
 Suggests:
     covr,