fix: generated board-related .conf files for build types

Before this fix the _construct_required_cmake_args function would
silently avoid adding the conf/<board>.conf to the OVERLAY_CONFIG
for the hw v2 names, since the below check would expect a name with the
'/' in it, which is not possible.

if os.path.isfile(board_conf):
    overlay_configs.append(f"{board}.conf")

CHANGELOG.md

@@ -6,6 +6,12 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 
 ## [Unreleased]
 
+### Fixed
+
+-   `east build` command silently dropped the board-related .conf files when build types 
+    were used. This bug was introduced in the v0.20.0. with the adoption of the new hardware 
+    model naming.
+
 ## [0.21.1] - 2024-08-20
 
 ### Fixed

src/east/workspace_commands/build_type_flag.py

@@ -48,6 +48,8 @@ def _construct_required_cmake_args(
     if board:
         # Sanitize the board input, user might gave hv version
         board = board.split("@")[0]
+        # Cleanup also hw v2 board names
+        board = board.replace("/", "_")
 
         # Location of the board file depends on the source_dir and prefix
         board_prefix = f"{source_dir}/{prefix}" if source_dir else f"{prefix}"

tests/test_release.py

@@ -515,3 +515,50 @@ def test_hw_model_v2_only_apps(west_workplace, monkeypatch, mocker):
         "release",
         expected_west_cmds=expected_hw_v2_only_apps_release_west_commands,
     )
+
+
+east_yaml_hw_model_v2_with_build_types = """
+apps:
+  - name: test_one
+    west-boards:
+      - nrf52840dk/nrf52840
+
+    build-types:
+      - type: debug
+        conf-files:
+          - debug.conf
+"""
+
+expected_hw_v2_with_build_types_release_west_commands = [
+    (
+        "build -b nrf52840dk/nrf52840 app -- -DCONF_FILE=conf/common.conf"
+        ' -DOVERLAY_CONFIG="conf/nrf52840dk_nrf52840.conf;conf/debug.conf"'
+        ' -DEAST_BUILD_TYPE="debug"'
+    ),
+    (
+        "build -b nrf52840dk/nrf52840 app -- -DCONF_FILE=conf/common.conf"
+        ' -DOVERLAY_CONFIG="conf/nrf52840dk_nrf52840.conf"'
+        ' -DEAST_BUILD_TYPE="release"'
+    ),
+]
+
+
+def test_hw_model_v2_with_build_types(west_workplace, monkeypatch, mocker):
+    """Running east release with build types, where the board names are in the new
+    hardware model v2 format, should work.
+    """
+    helpers.create_and_write(
+        west_workplace,
+        "east.yml",
+        east_yaml_hw_model_v2_with_build_types,
+    )
+
+    monkeypatch.setattr(east.workspace_commands.release_commands, "RUNNING_TESTS", True)
+
+    helper_test_against_west_run(
+        monkeypatch,
+        mocker,
+        west_workplace,
+        "release",
+        expected_west_cmds=expected_hw_v2_with_build_types_release_west_commands,
+    )