gnu: Add r-dir-expiry.

* gnu/packages/bioconductor.scm (r-dir-expiry): New variable.

gnu/packages/bioconductor.scm

@@ -13938,6 +13938,30 @@ (define-public r-genetclassifier
 interface to query the classifier.")
     (license license:gpl2+)))
 
+(define-public r-dir-expiry
+  (package
+    (name "r-dir-expiry")
+    (version "1.0.0")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (bioconductor-uri "dir.expiry" version))
+       (sha256
+        (base32
+         "05mk7iwzay1xrgvssbz7nyl5d1n03syalbk18lmjmbx05dy0cjik"))))
+    (properties `((upstream-name . "dir.expiry")))
+    (build-system r-build-system)
+    (propagated-inputs `(("r-filelock" ,r-filelock)))
+    (native-inputs `(("r-knitr" ,r-knitr)))
+    (home-page "https://bioconductor.org/packages/dir.expiry")
+    (synopsis "Managing expiration for cache directories")
+    (description
+     "This package implements an expiration system for access to versioned
+directories.  Directories that have not been accessed by a registered function
+within a certain time frame are deleted.  This aims to reduce disk usage by
+eliminating obsolete caches generated by old versions of packages.")
+    (license license:gpl3)))
+
 (define-public r-tximeta
   (package
     (name "r-tximeta")