Google vision API: Slow response times

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Please run down the following list and make sure you've tried the usual "quick fixes":

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#### Environment details

- OS: MacOS
- Ruby version: 3.3.6
- Gem name and version: google-cloud-vision (1.5.1)

#### Steps to reproduce

1. Call the API and pass an image
2. The API call works and I get the response, but the response time is huge (approx 77 seconds). If I use the Rest API, I get very quick response for the same image.

#### Code example

```
require "google/cloud/vision"
require "time"
require "base64"

# Initialize the Vision API client
vision = Google::Cloud::Vision.image_annotator

image_path = Rails.root.join("app", "assets", "images", "cookie.png")
image = File.open(image_path, "rb")

# Cloudinary URL of the image
# image_url = "https://res.cloudinary.com/dqstmox0s/image/upload/v1736173018/cookie_zqljqk.png"

# Start measuring time
start_time = Time.now

# Perform text detection (OCR) on the image from the Cloudinary URL
begin
puts "Calling Vision API..."
# Sending image URL for OCR
response = vision.text_detection image: image

# End measuring time
end_time = Time.now
duration = end_time - start_time

# Print the time it took
puts "OCR request took #{duration} seconds."

# The response contains multiple results in 'text_annotations'
if response.responses.any?
# Get the text annotations from the first response
annotations = response.responses.first.text_annotations

# Print the detected text
raw_text = annotations.first.description
split_text = raw_text.split("\n")
text_to_match = split_text[0]
puts "Detected text:"
p text_to_match
else
puts "No text annotations found."
end
rescue StandardError => e
puts "An error occurred: #{e.message}"
end
```

#### Full backtrace

```sh
Calling Vision API...
OCR request took 76.694712 seconds.
Detected text:
"Image text"
```

Could there be some kind of configuration issue? I was thinking which endpoint it's calling (Europe or US), but this seems to work properly with the generic endpoint when using the REST API.

Thanks for your help!