fix: specify branch in DESCRIPTION

Author: dshemetov

DESCRIPTION

@@ -1,6 +1,6 @@
 Package: epipredict
 Title: Basic epidemiology forecasting methods
-Version: 0.0.20
+Version: 0.0.21
 Authors@R: c(
     person("Daniel", "McDonald", , "[email protected]", role = c("aut", "cre")),
     person("Ryan", "Tibshirani", , "[email protected]", role = "aut"),
@@ -67,7 +67,7 @@ VignetteBuilder:
     knitr
 Remotes:
     cmu-delphi/epidatr,
-    cmu-delphi/epiprocess,
+    cmu-delphi/epiprocess@lcb/slide-improvements-2024-06,
     dajmcdon/smoothqr
 Config/testthat/edition: 3
 Encoding: UTF-8