Cannot read properties of null (reading 'accessKeyId')

Describe the bug

When the recently-added BTCEXP_S3_... variables are not defined, the current master (87fe724a357e29fef0dd433b6d065a2ac55a3aab) ends with following error:

> btc-rpc-explorer@3.3.0 start
> node ./bin/www

  btcexp:app Searching for config files... +0ms
  btcexp:app Config file not found at /home/be/.config/btc-rpc-explorer.env, continuing... +6ms
  btcexp:app Config file not found at /etc/btc-rpc-explorer/.env, continuing... +0ms
  btcexp:app Config file not found at /home/be/src/btc-rpc-explorer/.env, continuing... +1ms
  btcexp:app No config files found. Using all defaults. +0ms
/home/be/src/btc-rpc-explorer/node_modules/@janoside/app-utils/src/s3Utils.js:13
debugLog(`Using AWS Access Key: ${AWS.config.credentials.accessKeyId}`);
                                                         ^

TypeError: Cannot read properties of null (reading 'accessKeyId')
    at Object.<anonymous> (/home/be/src/btc-rpc-explorer/node_modules/@janoside/app-utils/src/s3Utils.js:13:58)
    at Module._compile (node:internal/modules/cjs/loader:1103:14)
    at Object.Module._extensions..js (node:internal/modules/cjs/loader:1155:10)
    at Module.load (node:internal/modules/cjs/loader:981:32)
    at Function.Module._load (node:internal/modules/cjs/loader:822:12)
    at Module.require (node:internal/modules/cjs/loader:1005:19)
    at require (node:internal/modules/cjs/helpers:102:18)
    at Object.<anonymous> (/home/be/src/btc-rpc-explorer/node_modules/@janoside/app-utils/index.js:4:17)
    at Module._compile (node:internal/modules/cjs/loader:1103:14)
    at Object.Module._extensions..js (node:internal/modules/cjs/loader:1155:10)
    at Module.load (node:internal/modules/cjs/loader:981:32)
    at Function.Module._load (node:internal/modules/cjs/loader:822:12)
    at Module.require (node:internal/modules/cjs/loader:1005:19)
    at require (node:internal/modules/cjs/helpers:102:18)
    at Object.<anonymous> (/home/be/src/btc-rpc-explorer/app.js:99:18)
    at Module._compile (node:internal/modules/cjs/loader:1103:14)

Environment (please complete the following information):

• Bitcoin Core / Node Version 23.0
• NodeJS Version v16.14.0
• Browser Google Chrome
• Code Version / Commit 87fe724a357e29fef0dd433b6d065a2ac55a3aab
• Installation Method “source code”

Configuration file content

No BTCEXP_S3 options set in the .env file. The Bitcoin Explorer works with following patch applied: https://github.com/jsarenik/btc-rpc-explorer/commit/768de3c182dd9ff275b16f730dcceea4b194e580

The '.env` file for ex.signet.bublina.eu.org:

BTCEXP_HOST=127.0.0.1
BTCEXP_PORT=3003
BTCEXP_BITCOIND_HOST=127.0.0.1
BTCEXP_BITCOIND_PORT=38332
BTCEXP_DEMO=true
BTCEXP_SLOW_DEVICE_MODE=true
BTCEXP_NO_RATES=true
BTCEXP_UI_HOME_PAGE_LATEST_BLOCKS_COUNT=6
BTCEXP_FILESYSTEM_CACHE_DIR=../../.cache/signet
BTCEXP_ADDRESS_API=electrum
BTCEXP_ELECTRUM_SERVERS=tls://signet-electrumx.wakiyamap.dev:50002
BTCEXP_ELECTRUM_TXINDEX=true
BTCEXP_UI_THEME=dark
BTCEXP_NO_INMEMORY_RPC_CACHE=true

To Reproduce

Steps to reproduce the behavior:

1. Do not set any BTCEXP_S3 options in the env file.
2. Start the Bitcoin Explorer with npm start.
3. See error.

[pointbiz]

I tested and works for me now.

[mat-h7]

I can also confirm that it is working for me now, thanks!