reduce test binary size and add missing webhook build

[oilbeater]

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What type of this PR

Examples of user facing changes:

• CI

Which issue(s) this PR fixes:

Fixes #(issue-number)

WHAT

🤖 Generated by Copilot at 8890c3a

Reduce binary size and include webhook tests in end-to-end build. The Makefile.e2e file was modified to add the -ldflags "-w -s" option to the ginkgo build commands and to include the ./test/e2e/webhook directory in the e2e-build target.

🤖 Generated by Copilot at 8890c3a

ginkgo build flags
strip the binaries for speed
webhook joins e2e-build

HOW

🤖 Generated by Copilot at 8890c3a

• Add -ldflags "-w -s" option to ginkgo build commands to strip debug information and symbol table from binaries and improve test performance and efficiency (link, )
• Include ./test/e2e/webhook directory in e2e-build target to build webhook tests (link)

[github-actions]

• The commit message is missing. Please add a descriptive commit message.
• It seems like the diff only modifies the Makefile.e2e file. Please make sure that this is intentional and there are no other changes that were missed.
• Consider adding comments to explain what each ginkgo build command does.
• The -ldflags "-w -s" option can potentially cause issues with debugging and profiling. Consider adding a comment explaining why it was added and if there are any alternatives or workarounds.