Revert "Adds on-call icon - [WEB-5395] (#25588)"

This reverts commit 1b45874.

config/_default/menus/main.en.yaml

@@ -2176,7 +2176,7 @@ menu:
       weight: 10
     - name: On-Call
       url: service_management/on-call/
-      pre: on-call
+      pre: incidents
       parent: service_management_heading
       identifier: oncall
       weight: 30000

go.mod

@@ -3,7 +3,7 @@ module documentation
 go 1.14
 
 require (
-	github.com/DataDog/websites-modules v1.4.188 // indirect
+	github.com/DataDog/websites-modules v1.4.187 // indirect
 	github.com/DataDog/websites-sources v0.0.0-20240828113530-52633d72da19 // indirect
 )
 

go.sum

@@ -1,4 +1,4 @@
-github.com/DataDog/websites-modules v1.4.188 h1:qiZ3rmYV8M+nh1OBKzXlhpfAQIMANNT+9IPJVUpsdtg=
-github.com/DataDog/websites-modules v1.4.188/go.mod h1:CcQxAmCXoiFr3hNw6Q+1si65C3uOP1gB+7aX4S3h+CQ=
+github.com/DataDog/websites-modules v1.4.187 h1:I0CwJobhsK54qJe2QL44S3kfBJEa/7G2LFTu6j837IE=
+github.com/DataDog/websites-modules v1.4.187/go.mod h1:CcQxAmCXoiFr3hNw6Q+1si65C3uOP1gB+7aX4S3h+CQ=
 github.com/DataDog/websites-sources v0.0.0-20240828113530-52633d72da19 h1:hWHa2AWZnGf9rTTp8EgCcQ12blRDGAkzru8mcm8WJ3M=
 github.com/DataDog/websites-sources v0.0.0-20240828113530-52633d72da19/go.mod h1:RvGhXV0uQC6Ocs+n84QyL97kows6vg6VG5ZLQMHw4Fs=