Expose source_url in API::Entities::BulkImport

What does this MR do and why?

This MR adds source_url attribute to API::Entities::BulkImport which is fetched via BulkImports::Configiration#url.

Mentions #462998 (closed)

SQL Query

finder = BulkImports::ImportsFinder.new(user: User.first, params: { include_configuration: true}) finder.execute

# existing, unchanged query to load imports
SELECT "bulk_imports".* FROM "bulk_imports" WHERE "bulk_imports"."user_id" = 1

# new query to load configurations
SELECT "bulk_import_configurations".* FROM "bulk_import_configurations" WHERE "bulk_import_configurations"."bulk_import_id" IN (1, 3, 4, 5, 6)

Execution plan (picked 200 configurations as an example)

explain SELECT "bulk_import_configurations".* FROM "bulk_import_configurations" WHERE "bulk_import_configurations"."bulk_import_id" IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193, 194, 195, 196, 197, 198, 199, 200)

 Index Scan using index_bulk_import_configurations_on_bulk_import_id on public.bulk_import_configurations  (cost=0.29..147.58 rows=200 width=180) (actual time=0.023..2.017 rows=164 loops=1)
   Index Cond: (bulk_import_configurations.bulk_import_id = ANY ('{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,198,199,200}'::integer[]))
   Buffers: shared hit=417 read=4
   I/O Timings: read=1.784 write=0.000

Recommendations:
✅ Looks good
Summary:

  
Time: 3.217 ms  
  - planning: 1.138 ms  
  - execution: 2.079 ms  
    - I/O read: 1.784 ms  
    - I/O write: 0.000 ms  
  
Shared buffers:  
  - hits: 417 (~3.30 MiB) from the buffer pool  
  - reads: 4 (~32.00 KiB) from the OS file cache, including disk I/O  
  - dirtied: 0  
  - writes: 0  

Query plan link: https://console.postgres.ai/gitlab/gitlab-production-main/sessions/30240/commands/93809

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