chore: remove temporary compile_binary diagnostics

The go env / vendor/modules.txt diagnostic lines added in the previous
commit have served their purpose. Retain the Open3.capture2e change so
that go build errors remain visible in the test failure message.

Author: driv3r

test/helpers/ghostferry_helper.rb

@@ -143,17 +143,6 @@ def compile_binary
 
       @logger.debug("compiling test binary to #{@compiled_binary_path}")
 
-      # Diagnostics: dump Go environment before building so that CI failures
-      # show the actual cause rather than the generic "could not compile" message.
-      # Captures GOMOD / GOWORK / GOFLAGS to detect unexpected workspace or
-      # vendor-mode activation, and checks for a repo-level vendor/modules.txt.
-      go_env, _  = Open3.capture2e("go", "env", "GOMOD", "GOWORK", "GOFLAGS")
-      repo_root  = File.expand_path("../..", __dir__)
-      vendor_txt = File.join(repo_root, "vendor", "modules.txt")
-      @logger.debug("[compile_binary] go env: #{go_env.strip}")
-      @logger.debug("[compile_binary] repo_root: #{repo_root}")
-      @logger.debug("[compile_binary] vendor/modules.txt present: #{File.exist?(vendor_txt)}")
-
       # Use capture2e so that go build stderr is included in the raised error
       # message rather than being swallowed by the test runner.
       output, status = Open3.capture2e(