Increase default trie cache size to 1GiB (#6546)

The default trie cache size before was set to `64MiB`, which is quite
low to achieve real speed ups. `1GiB` should be a reasonable number as
the requirements for validators/collators/full nodes are much higher
when it comes to minimum memory requirements. Also the cache will not
use `1GiB` from the start and fills over time. The setting can be
changed by setting `--trie-cache-size BYTE_SIZE`.

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Co-authored-by: GitHub Action <[email protected]>