Update diesel requirement from 1.4.5 to 2.0.3

[dependabot]

Updates the requirements on diesel to permit the latest version.

Release notes

Sourced from diesel's releases.

Diesel 2.0.3

Fixed

• Fixed a bug with our transaction manager implementation that caused by marking transactions as broken which could be recovered.
• Fixed an issue with the combination of BoxableExpression and order clauses

Changelog

Sourced from diesel's changelog.

[2.0.3] 2023-01-24

Fixed

• Fixed a bug with our transaction manager implementation that caused by marking transactions as broken which could be recovered.
• Fixed an issue with the combination of BoxableExpression and order clauses

[2.0.2] 2022-10-11

Fixed

• Reverted a fix from the 2.0.1 release that breaks valid INSERT … ON CONFLICT queries

[2.0.1] 2022-10-07

Fixed

• Fixed an issue with diesel_cli generating incompatible type names for the generate_missing_sql_type_definitions feature on PostgreSQL
• Fixed an issue how diesel_cli handles sqlite urls while checking if a given database exists
• Fixed an issue with PgConnection becoming unusable after hitting a database error in certain situations
• Fixed an issue with diesel generating invalid SQL for certain INSERT … ON CONFLICT queries
• Fixed diesel_derives generating code that triggers the disabled by default unused_qualifications lint

[2.0.0] 2022-08-29

Added

• MysqlConnection::establish is able to initiate an SSL connection while specifying certificate roots. The database URL should contain an ssl_ca parameter with a path pointing to the certificate roots. See docs if desired.

• MysqlConnection::establish is able to initiate an SSL connection. The database URL should contain ssl_mode parameter with a value of the MySQL client command option --ssl-mode if desired.

• Connection and SimpleConnection traits are implemented for a broader range of r2d2::PooledConnection<M> types when the r2d2 feature is enabled.

• Added DatabaseErrorKind::ReadOnlyTransaction to allow applications to handle errors caused by writing when only allowed to read.

• All expression methods can now be called on expressions of nullable types.

• Added BoxedSqlQuery. This allows users to do a variable amount of .sql or .bind calls without changing the underlying type.

• Added .sql to SqlQuery and UncheckedBind to allow appending SQL code to an existing query.

• The MacAddr SQL type can now be used without enabling the network-address feature.

• Added support for SQLite's UPSERT. You can use this feature above SQLite version 3.24.0.

... (truncated)

Commits

• eedc141 Merge pull request #3486 from weiznich/backport_fixes
• c11a7c9 Update CHANGELOG.md
• 0a012d5 Update CHANGELOG.md
• 702f932 Remove the warnings check from the CI setup for the 2.0.x branch
• d9d1f4e Prepare a 2.0.3 release
• bb2e50c Update the mysql crate to fix the benchmark build failure
• 203e10d Update compile tests
• 793a91a Fix #3412
• 96e8902 Readd removed functions for backward compatibility reasons
• 7ac10b4 minor doc improvement
• Additional commits viewable in compare view

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[dependabot]

Superseded by #47.