Unlock build using Elixir 1.15 (#4726)

* Unlock support for Elixir 1.15 builds
* Include elixir build folders into the make clean target

Makefile

@@ -461,11 +461,14 @@ install: release
 # target: clean - Remove build artifacts
 clean:
 	@$(REBAR) -r clean
+	@mix clean --deps
 	@rm -rf .rebar/
+	@rm -rf _build
 	@rm -f bin/couchjs
 	@rm -f bin/weatherreport
 	@rm -rf src/*/ebin
 	@rm -rf src/*/.rebar
+	@rm -rf src/*/_build
 	@rm -rf src/*/priv/*.so
 	@rm -rf src/couch/priv/{couchspawnkillable,couchjs}
 	@rm -rf share/server/main.js share/server/main-ast-bypass.js share/server/main-coffee.js

Makefile.win

@@ -418,10 +418,13 @@ install: release
 # target: clean - Remove build artifacts
 clean:
 	@$(REBAR) -r clean
+	-@mix clean --deps
 	-@rmdir /s/q .rebar
+	-@rmdir /s/q _build
 	-@del /f/q bin\couchjs.exe
 	-@rmdir /s/q src\*\ebin
 	-@rmdir /s/q src\*\.rebar
+	-@rmdir /s/q src\*\_build
 	-@del /f/q/s src\*.dll
 	-@del /f/q src\couch\priv\*.exe
 	-@del /f/q share\server\main.js share\server\main-ast-bypass.js share\server\main-coffee.js

mix.exs

@@ -61,6 +61,7 @@ defmodule CouchDBTest.Mixfile do
       consolidate_protocols: Mix.env() not in [:test, :dev, :integration],
       test_paths: get_test_paths(Mix.env()),
       elixirc_paths: elixirc_paths(Mix.env()),
+      prune_code_paths: false,
       test_coverage: [
         tool: CoverTool,
         dirs: get_coverage_paths(),