Remove legacy generate and bundle cmds

Removed legacy "generate csv/packagemanifests/bundle", and "bundle create/validate" commands.
Also removed associated scaffolding packages for these commands in "internal/generate/olm-catalog".

changelog/fragments/rm-legacy-bundle-cmds.yaml

@@ -0,0 +1,11 @@
+# entries is a list of entries to include in
+# release notes and/or the migration guide
+entries:
+  - description: >
+      Remove legacy "bundle create/validate" commands
+    kind: "removal"
+    # Is this a breaking change?
+    breaking: true
+    migration:
+      header: Remove legacy "bundle create/validate" commands
+      body: TBD

changelog/fragments/rm-legacy-gen-bundle.yaml

@@ -0,0 +1,11 @@
+# entries is a list of entries to include in
+# release notes and/or the migration guide
+entries:
+  - description: >
+      Remove legacy generate bundle command
+    kind: "removal"
+    # Is this a breaking change?
+    breaking: true
+    migration:
+      header: Remove legacy generate bundle command
+      body: TBD

changelog/fragments/rm-legacy-gen-csv.yaml

@@ -0,0 +1,11 @@
+# entries is a list of entries to include in
+# release notes and/or the migration guide
+entries:
+  - description: >
+      Remove legacy generate csv command
+    kind: "removal"
+    # Is this a breaking change?
+    breaking: true
+    migration:
+      header: Remove legacy generate csv command
+      body: TBD

changelog/fragments/rm-legacy-gen-packagemanifests.yaml

@@ -0,0 +1,11 @@
+# entries is a list of entries to include in
+# release notes and/or the migration guide
+entries:
+  - description: >
+      Remove legacy generate packagemanifests command
+    kind: "removal"
+    # Is this a breaking change?
+    breaking: true
+    migration:
+      header: Remove legacy generate packagemanifests command
+      body: TBD

cmd/operator-sdk/bundle/cmd.go

@@ -44,19 +44,6 @@ https://github.com/operator-framework/operator-registry/blob/master/docs/design/
 	return cmd
 }
 
-func NewCmdLegacy() *cobra.Command {
-	cmd := newCmd()
-	cmd.Long += `
-More information about the integration with OLM via SDK:
-https://sdk.operatorframework.io/docs/olm-integration/legacy
-`
-	cmd.AddCommand(
-		newCreateCmd(),
-		newValidateCmdLegacy(),
-	)
-	return cmd
-}
-
 func NewCmd() *cobra.Command {
 	cmd := newCmd()
 	cmd.Long += `

cmd/operator-sdk/bundle/cmd_test.go

@@ -30,16 +30,4 @@ var _ = Describe("Running a bundle command", func() {
 			Expect(subcommands[0].Use).To(Equal("validate"))
 		})
 	})
-
-	Describe("NewCmdLegacy", func() {
-		It("builds and returns a cobra command with the correct subcommands", func() {
-			cmd := NewCmdLegacy()
-			Expect(cmd).NotTo(BeNil())
-
-			subcommands := cmd.Commands()
-			Expect(len(subcommands)).To(Equal(2))
-			Expect(subcommands[0].Use).To(Equal("create"))
-			Expect(subcommands[1].Use).To(Equal("validate"))
-		})
-	})
 })