Honor build_tags in config (open-telemetry#11156)

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Ex. Adding a feature - Explain what this achieves.-->
#### Description

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#### Link to tracking issue
Fixes #

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#### Testing

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#### Documentation

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.chloggen/fixbuildtags.yaml

@@ -0,0 +1,20 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: 'bug_fix'
+
+# The name of the component, or a single word describing the area of concern, (e.g. otlpreceiver)
+component: builder
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Honor build_tags in config
+
+# One or more tracking issues or pull requests related to the change
+issues: [11156]
+
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: [user]

cmd/builder/internal/builder/config_test.go

@@ -153,6 +153,7 @@ func TestNewDefaultConfig(t *testing.T) {
 	assert.NoError(t, cfg.SetGoPath())
 	require.NoError(t, cfg.Validate())
 	assert.False(t, cfg.Distribution.DebugCompilation)
+	assert.Empty(t, cfg.Distribution.BuildTags)
 }
 
 func TestNewBuiltinConfig(t *testing.T) {
@@ -198,6 +199,18 @@ func TestSkipGoInitialization(t *testing.T) {
 	assert.Zero(t, cfg.Distribution.Go)
 }
 
+func TestBuildTagConfig(t *testing.T) {
+	cfg := Config{
+		Distribution: Distribution{
+			BuildTags: "customTag",
+		},
+		SkipCompilation: true,
+		SkipGetModules:  true,
+	}
+	require.NoError(t, cfg.Validate())
+	assert.Equal(t, "customTag", cfg.Distribution.BuildTags)
+}
+
 func TestDebugOptionSetConfig(t *testing.T) {
 	cfg := Config{
 		Distribution: Distribution{

cmd/builder/internal/builder/main_test.go

@@ -289,6 +289,18 @@ func TestGenerateAndCompile(t *testing.T) {
 				return cfg
 			},
 		},
+		{
+			name: "Build Tags Compilation",
+			cfgBuilder: func(t *testing.T) Config {
+				cfg := newTestConfig()
+				err := cfg.SetBackwardsCompatibility()
+				require.NoError(t, err)
+				cfg.Distribution.OutputPath = t.TempDir()
+				cfg.Replaces = append(cfg.Replaces, replaces...)
+				cfg.Distribution.BuildTags = "customTag"
+				return cfg
+			},
+		},
 		{
 			name: "Debug Compilation",
 			cfgBuilder: func(t *testing.T) Config {

cmd/builder/internal/command.go

@@ -209,5 +209,6 @@ func applyCfgFromFile(flags *flag.FlagSet, cfgFromFile builder.Config) {
 	if !flags.Changed(distributionModuleFlag) && cfgFromFile.Distribution.Module != "" {
 		cfg.Distribution.Module = cfgFromFile.Distribution.Module
 	}
+	cfg.Distribution.BuildTags = cfgFromFile.Distribution.BuildTags
 	cfg.Distribution.DebugCompilation = cfgFromFile.Distribution.DebugCompilation
 }