[chore] remove internal unused unstable functionality (#16711)

This functionality was added only for receivers (incomplete) and has not been used for at least 1y. Propose to remove since we always can add it back.

Signed-off-by: Bogdan Drutu <bogdandrutu@gmail.com>

Makefile

@@ -56,14 +56,14 @@ all-groups:
 	@echo "\nother: $(OTHER_MODS)"
 
 .PHONY: all
-all: install-tools all-common goporto multimod-verify gotest otelcontribcol otelcontribcol-unstable
+all: install-tools all-common goporto multimod-verify gotest otelcontribcol
 
 .PHONY: all-common
 all-common:
 	@$(MAKE) $(FOR_GROUP_TARGET) TARGET="common"
 
 .PHONY: e2e-test
-e2e-test: otelcontribcol otelcontribcol-unstable otelcontribcol-testbed
+e2e-test: otelcontribcol otelcontribcol-testbed
 	$(MAKE) -C testbed run-tests
 
 .PHONY: unit-tests-with-cover
@@ -270,12 +270,6 @@ otelcontribcol:
 	GO111MODULE=on CGO_ENABLED=0 $(GOCMD) build -trimpath -o ./bin/otelcontribcol_$(GOOS)_$(GOARCH)$(EXTENSION) \
 		$(BUILD_INFO) -tags $(GO_BUILD_TAGS) ./cmd/otelcontribcol
 
-# Build the Collector executable, including unstable functionality.
-.PHONY: otelcontribcol-unstable
-otelcontribcol-unstable:
-	GO111MODULE=on CGO_ENABLED=0 $(GOCMD) build -trimpath -o ./bin/otelcontribcol_unstable_$(GOOS)_$(GOARCH)$(EXTENSION) \
-		$(BUILD_INFO) -tags $(GO_BUILD_TAGS),enable_unstable ./cmd/otelcontribcol
-
 # Build the Collector executable, with only components used in testbed.
 .PHONY: otelcontribcol-testbed
 otelcontribcol-testbed:

internal/components/components.go

@@ -291,7 +291,6 @@ func Components() (component.Factories, error) {
 		vcenterreceiver.NewFactory(),
 		zipkinreceiver.NewFactory(),
 	}
-	receivers = append(receivers, extraReceivers()...)
 	factories.Receivers, err = component.MakeReceiverFactoryMap(receivers...)
 	if err != nil {
 		return component.Factories{}, err