[Http] Reply with structured issues when client accepts json data

[UgnineSirdis]

Changelog entry

When client says that it expects data in json format, send issues in json format instead of html.
It improves issues display in YDB UI

Changelog category

• Improvement

Additional information

...

[github-actions]

⚪ 2024-08-13 07:12:22 UTC Pre-commit check for d959d76 has started.
⚪ 2024-08-13 07:14:59 UTC Build linux-x86_64-release-clang14 is running...
🟢 2024-08-13 07:39:02 UTC Build successful.

[github-actions]

⚪ 2024-08-13 07:14:46 UTC Pre-commit check for d959d76 has started.
⚪ 2024-08-13 07:17:25 UTC Build linux-x86_64-relwithdebinfo is running...
🟢 2024-08-13 08:06:01 UTC Build successful.
⚪ 2024-08-13 08:06:17 UTC Tests are running...
🔴 2024-08-13 09:49:06 UTC Some tests failed, follow the links below.

Test history | Test log

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
39652	34418	0	4	5220	10

🟢 2024-08-13 09:49:49 UTC ydbd size 8.1 GiB changed* by +41.7 KiB, which is < 100.0 KiB vs stable-24-3: OK

ydbd size dash	stable-24-3: 282df40	merge: d959d76	diff	diff %
ydbd size	8 723 846 368 Bytes	8 723 889 040 Bytes	+41.7 KiB	+0.000%
ydbd stripped size	476 904 968 Bytes	476 909 832 Bytes	+4.8 KiB	+0.001%

^{*please be aware that the difference is based on comparing your commit and the last completed build from the post-commit, check comparation}

[github-actions]

⚪ 2024-08-13 07:15:22 UTC Pre-commit check for d959d76 has started.
⚪ 2024-08-13 07:18:02 UTC Build linux-x86_64-release-asan is running...
🟢 2024-08-13 07:51:28 UTC Build successful.
⚪ 2024-08-13 07:51:44 UTC Tests are running...
🔴 2024-08-13 09:41:41 UTC Some tests failed, follow the links below.

Test history | Test log

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
11125	11077	0	10	25	13

🟢 2024-08-13 09:42:24 UTC ydbd size 5.5 GiB changed* by +13.5 KiB, which is < 100.0 KiB vs stable-24-3: OK

ydbd size dash	stable-24-3: 282df40	merge: d959d76	diff	diff %
ydbd size	5 904 309 416 Bytes	5 904 323 200 Bytes	+13.5 KiB	+0.000%
ydbd stripped size	1 480 253 632 Bytes	1 480 249 184 Bytes	-4.3 KiB	-0.000%

^{*please be aware that the difference is based on comparing your commit and the last completed build from the post-commit, check comparation}