Use CheckHTTP in Go SDK

[sbienkow-ninja]

Closes: #1650

Summary by OpenAI

New Feature:
- Added HTTP middleware for flow control in Aperture Go SDK
- Introduced new `middlewares` package and moved related functions
- Implemented `StartHTTPFlow` method in the `Client` interface

Bug fix:
- Added null check before closing response body in `checkhttp`

Documentation:
- Updated documentation for using HTTP middleware with Aperture Go SDK
- Provided examples for setting up middleware on an HTTP server

🎉 A middleware we've brought, to control the flow,
In Aperture Go SDK, it's now set to go.
With patterns and checks, our requests find their way,
Celebrate this PR, for a brighter day! 🌟

[github-actions]

🤖 OpenAI

Here is the summary of changes:

The diff introduces a new package middlewares and moves existing middleware-related code to it. It adds an HTTP middleware using CheckHTTP from the Aperture library for flow control in the Go SDK. The changes also include updates to the Flow interface, addition of a new method StartHTTPFlow, and documentation on how to use the middleware with examples.

Files	Summary
.pre-commit-config.yaml	Updates Python version used by the black hook configuration.
api/Makefile, cmd/sdk-validator/main.go	Adds a new directory checkhttp, copies files into it, and adds a null check before closing the response body.
sdks/aperture-go/sdk/middlewares/grpc.go, sdks/aperture-go/sdk/middlewares/http.go, ...	Introduces a new package middlewares, moves existing middleware-related code to it, and adds new functions for gRPC and HTTP middlewares.
sdks/aperture-go/example/main.go, sdks/aperture-go/sdk/client.go, ...	Adds a new method StartHTTPFlow, updates the Flow interface, and implements middleware for HTTP requests using CheckHTTP.
docs/content/get-started/integrations/flow-control/sdk/go/manual.md, ...	Adds documentation for using HTTP middleware with the Aperture Go SDK, provides examples, updates the Dockerfile, and explains how to set middleware for an HTTP server with and without regexp patterns.

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Files ignored due to filter (8)

Ignored files

• sdks/aperture-go/gen/proto/flowcontrol/checkhttp/v1/checkhttp.pb.go
• sdks/aperture-go/gen/proto/flowcontrol/checkhttp/v1/checkhttp.pb.gw.go
• sdks/aperture-go/gen/proto/flowcontrol/checkhttp/v1/checkhttp.pb.json.go
• sdks/aperture-go/gen/proto/flowcontrol/checkhttp/v1/checkhttp.pb.validate.go
• sdks/aperture-go/gen/proto/flowcontrol/checkhttp/v1/checkhttp_deepcopy.gen.go
• sdks/aperture-go/gen/proto/flowcontrol/checkhttp/v1/checkhttp_grpc.pb.go
• sdks/aperture-go/go.mod
• sdks/aperture-go/go.sum

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In the recent run, only the files that changed from the base of the PR and between 56d3a8639c7b2fb557460e8d8cb31c2a601af954 and c571c22717da8741b9c68a7f0e241e82b54fa330 commits were reviewed.

Files not reviewed due to simple changes (6)

Skipped review in the recent run

• .pre-commit-config.yaml
• cmd/sdk-validator/main.go
• docs/content/get-started/integrations/flow-control/sdk/go/manual.md
• sdks/aperture-go/Dockerfile
• sdks/aperture-go/sdk/flowstatus.go
• sdks/aperture-go/sdk/middlewares/utils.go

[hdkshingala]

As discussed with @IridiumOxide for Java SDK, we should also add an example for use of CheckHTTP and have helper method for CheckHTTPRequest generation. Ref - https://fluxninja.slack.com/archives/C043WKQ6212/p1684498268031049

But this can go in a separate PR later.