How to get list of all databases using MongodbClient class. (C# application)

exec SearchAllDatabases @SearchTerm = '%B2%'

  CREATE PROCEDURE dbo.SearchAllDatabases
  @SearchTerm NVARCHAR(255) = NULL
AS
BEGIN
  SET NOCOUNT ON;
SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;

IF @SearchTerm IS NULL OR @SearchTerm NOT LIKE N'%[^%^_]%'
  BEGIN
    RAISERROR(N'Please enter a valid search term.', 11, 1);
RETURN;
  END

  CREATE TABLE #results
  (
    [database]   SYSNAME,
    [schema]     SYSNAME,
    [table]      SYSNAME,
    [column]     SYSNAME,
    ExampleValue NVARCHAR(1000)
  );

  DECLARE
    @DatabaseCommands  NVARCHAR(MAX) = N'', 
    @ColumnCommands NVARCHAR(MAX) = N'';

  SELECT @DatabaseCommands = @DatabaseCommands + N'
    EXEC ' + QUOTENAME(name) + '.sys.sp_executesql
        @ColumnCommands, N''@SearchTerm NVARCHAR(MAX)'', @SearchTerm;'
    FROM sys.databases
    WHERE database_id  > 4  -- non-system databases
      AND[state]      = 0-- online
      AND user_access  = 0; -- multi-user

    SET @ColumnCommands = N'DECLARE @q NCHAR(1),
          @SearchCommands NVARCHAR(MAX);

SELECT @q = NCHAR(39),
  @SearchCommands = N''DECLARE @VSearchTerm VARCHAR(255) = @SearchTerm;'';

    SELECT @SearchCommands = @SearchCommands + CHAR(10) + N''

      SELECT TOP(1)
        [db]     = DB_NAME(),
        [schema] = N'' + @q + s.name + @q + '', 
        [table]  = N'' + @q + t.name + @q + '',
        [column] = N'' + @q + c.name + @q + '',
        ExampleValue = LEFT('' + QUOTENAME(c.name) + '', 1000)
      FROM '' + QUOTENAME(s.name) + ''.'' + QUOTENAME(t.name) + ''
      WHERE '' + QUOTENAME(c.name) + N'' LIKE @'' + CASE
        WHEN c.system_type_id IN(35, 167, 175) THEN ''V'' 
        ELSE '''' END + ''SearchTerm;'' 

    FROM sys.schemas AS s
    INNER JOIN sys.tables AS t
    ON s.[schema_id] = t.[schema_id]
    INNER JOIN sys.columns AS c
    ON t.[object_id] = c.[object_id]
    WHERE c.system_type_id IN (35, 99, 167, 175, 231, 239)
      AND c.max_length >= LEN(@SearchTerm);

PRINT @SearchCommands;
EXEC sys.sp_executesql @SearchCommands,
  N''@SearchTerm NVARCHAR(255)'', @SearchTerm;';

  INSERT #Results
  (
    [database],
    [schema],
    [table],
    [column],
    ExampleValue
  )
  EXEC[master].sys.sp_executesql @DatabaseCommands,
   N'@ColumnCommands NVARCHAR(MAX), @SearchTerm NVARCHAR(255)', 
    @ColumnCommands, @SearchTerm;

  SELECT[Searched for] = @SearchTerm;

  SELECT[database],[schema],[table],[column],ExampleValue
FROM #Results 
    ORDER BY[database],[schema],[table],[column];
END
GO

public class ProjectsContext : IProjectsContext {
    private const string ProjectsCollectionName = "Projects";
    private readonly IMongoDatabase database;
    private IMongoCollection<Project> projects;

    public ProjectsContext(IMongoDatabase database) {
        this.database = database;
    }

    public IMongoCollection<Project> Projects {
        get {
            if (projects is null)
                projects = database.GetCollection<Project>(ProjectsCollectionName);
            return projects;
        }
    }
}

//...ConfigureServices

services.AddScoped<IMongoDatabase>(sp => {
    var dbParams = sp.GetRequiredService<IDatabaseParameters>();
    var client = new MongoClient(dbParams.ConnectionString);
    return client.GetDatabase(dbParams.DatabaseName);
});

//...

[Fact(DisplayName = "Create a Project Context")]
public void CreateProjectContext() {
    // Arrange
    var collectionMock = Mock.Of<IMongoCollection<Project>>();
    var dbMock = new Mock<IMongoDatabase>();
    dbMock.Setup(_ => _.GetCollection<Project>(It.IsAny<string>()))
        .Returns(collectionMock);

    // Act
    var result = new ProjectsContext(dbMock.Object);

    // Assert
    result.Should().NotBeNull()
        .And.BeAssignableTo<IProjectsContext>();
    //Write a test to assert the ProjectCollection
    result.Projects.Should().Be(collectionMock);
}